As we move towards the end of 2015, the tidal wave that is Star Wars: The Force Awakens is looming ever closer and waiting to crash upon the shores. As the first theatrical release to come out of Disney's $4.05 billion acquisition of Lucasfilm, there is a huge amount of anticipation surrounding the movie, not to mention a slate of sequels and spinoffs - one of which is already filming. If there ever was a movie that was immune to box office failure, The Force Awakens might be it.

Although there was initial doubt that it would ever be a success, in hindsight it's easy to see why the original Star Wars managed to capture the imaginations (and wallets) of hardcore sci-fi fans and casual moviegoers alike when it was released in 1977. The film hits so many of the notes that have become mainstays of Hollywood blockbusters: it has a likeable everyman hero with humble origins and a great destiny; a beautiful and capable princess; a roguish bad boy; a struggle between the forces of good and evil; a story of underdogs taking on a mighty empire - all coupled with revolutionary (for the time) special effects.

As explained by economics expert Virginia Postrel, Hollywood operates according to the Pareto principle: the majority of profit comes from a minority of movies that do massively well at the box office, so there is no such thing as an 'average' movie. Because each of these explosive hits is unique and finds its own path into the hearts of audiences, it's impossible to look at them all as one big group and reverse-engineer a foolproof plan for success.

Even after a century of gathering knowledge about what audiences want, Hollywood is still prone to box office disasters that make the magic solution seem as elusive as ever. Why did John Carter hit the ground hard and Guardians of the Galaxy soar above expectations? Why did Jack the Giant Slayer sink like a stone, while Maleficent's success broke open the floodgates of live-action Disney remakes? Is DC's cinematic universe destined for the same success as Marvel's? Will the new Star Wars trilogy be everything that Disney hoped for?

One person whose job it is to answer such questions is Vincent Bruzzese, a veteran of entertainment market research whose company, C4, offers clients a breakdown of their scripts based on over a decade of research into what audiences want to see. He and his colleagues have provided feedback for scripts of over 50 films that have been released over the past few years. Bruzzese posits that during the century in which Hollywood has been trying to perfect the art of making money, audiences have become used to certain "micro-trends" in their movies. They've come to expect them and - crucially - to object when a movie strays from established patterns.

The Rules

The masked intruders in The Strangers

"If you have a horror film with multiple killers, the multiple killers have to be completely insane or else the audience objects," Bruzzese offers as an example. "By insane I mean they can't have any motive whatsoever... It has to be kind of like The Strangers, where their only motive is to kill the protagonist."

Movie enthusiasts and film critics alike may bristle at the suggestion that years of watching the latest studio fodder has conditioned them with a Pavlovian response - expecting a treat to follow a bell ring and protesting if something unexpected happens. After all, "predictable" is widely used as a pejorative term in reviews. Yet Bruzzese isn't the only industry expert who has come to the conclusion that successful movies need to follow tried-and-tested patterns.

Kathryn Arnold is a consultant and expert witness specializing in cases involving the film and entertainment industry, whose expertise stems from years of developing and producing feature films. Though her current day-to-day work no longer involves reading through screenplays, Arnold is still easily able to rattle off the rules for writing a Hollywood script:

"You're supposed to know who your characters are and what the main plot of the story is within the first ten pages [of the script]. And then... by the end of the act break, around page 30, that's where the story twists... By the end of those 30 pages you know exactly what the rest of the story's going to be. And then there's usually some kind of twist in the middle of the second act, and then of course at the end of the second act everything falls apart and you have to put it back together in Act 3."

Hearing it laid out like that, it's easy to see this pattern in a plethora of blockbuster films. Even just looking at the Marvel Cinematic Universe, the one-two punch of everything falling apart at the end of Act 2 and being rebuilt in Act 3 can be seen over and over again: Thor failing to lift Mjolnir, learning humility, and then reuniting with the Warriors Three to defeat the Destroyer; the Avengers being blown apart during the attack in the helicarrier and then teaming up to avenge Phil Coulson's death; the Guardians of the Galaxy being crushed in a battle with Ronan the Destroyer, then finally settling their differences and launching into a lock-and-load montage. Even if they're not consciously aware of it, any regular consumer of Hollywood movies will know these narrative 'rules', and may feel unsettled if they're not followed.

Guardians of the Galaxy full team

So what about movies that deliberately subvert audience expectations, and are praised for it? The Cabin in the Woods is one such example, with a 92% rating on Rotten Tomatoes and a 72% rating on Metacritic. Yet as Bruzzese points out, The Cabin in the Woods was a box office flop, with a worldwide gross of just $66.5 million.

"The reason it didn't do well is because it crossed over three different horror genres, where you had a horror spoof element to it... then cross into this horror haunting or supernatural idea, and then you also have this element where it is a pure killer - not supernatural - source of evil. And then you go to this apocalyptic ending. All of these give marketing difficulty in terms of how and who to market the movie to, and it hurts word of mouth in terms of how you describe the movie to others. And it does not hold up narratively. So you have a movie that they spent a great deal of money on, and there's a great deal of anticipation for, but because it was narratively flawed it does well below the expected box office of the genre."

A lot of people loved The Cabin in the Woods, but it's easy to see how its unconventional structure made it difficult to market. At the time when it was in theaters, word of mouth often took the form of, 'I don't want to tell you too much about it, and you shouldn't read anything about it - just go and see it,' which wasn't the most compelling sell. Comparatively, Wes Craven's Scream spoofed the slasher genre while structurally being a very traditional slasher film. Perhaps that's why Scream performed so much better at the box office.

Next: The Making of a Hollywood Script

The Making of a Hollywood Script

Nicolas Cage in Adaptation

Between the directors who have dropped out of Marvel movie projects and the all-around disaster that was Josh Trank's clash with 20th Century Fox during the making of Fantastic Four, even casual moviegoers can't help but be aware of how much oversight and interference there is in the creative process of making a studio film. It might seem as though franchising is to blame for this, but Bruzzese says that even original scripts will be heavily transformed as they make the journey from the desk of an eager screenwriter into the hands of actors when filming begins - and even beyond.

The concept of what C4 does - taking a raw, virginal screenplay into which the writer has poured their heart and soul, and applying market research and statistics to decide how it should be changed to please studio executives and audiences - might sound abhorrent, especially to a budding screenwriter. "When you don't know what it is, it sounds like you're trying to algorithm art," Bruzzese says, explaining that it's common for screenwriters to have an initially negative reaction.

Yet the film industry is, generally speaking, not a place where raw, virginal screenplays ever emerge intact. In fact, the chances of them emerging at all are slim. "The sad thing is that if you look at the actual process in this industry, it's ridiculous," Bruzzese says. A good script needs to fall onto the desk of the right person working in the right agency, who needs to be in a good enough mood to react positively to it. Then, if the screenwriter is lucky enough to see their script optioned, "the first thing that's going to happen is a rewrite's going to occur, so whoever options it can put their stamp on it" - a rewrite that may or may not involve the original writer at all. Once a director is hired, the director will put their own stamp on the film, and even after production is complete the changes won't stop, because that's when the film is screened for test audiences who suggest their own changes to the edit:

"That's what people are defending, is the artistic process. What we're trying to do is go to the writer at a very early stage and say, 'Look, we can provide you an early crystal ball here on what audience response is going to be based on your idea.' We know you love your baby and we know you think it's the best thing ever and it's the most wonderful story ever told... but right now you have the most control over that script that you ever will. In the future there'll be fifty people in a room - if you're lucky - who are all trying to make changes to it. We're able to tell you the kind of changes they're going to try to make and give you that information early."

Movies Based on Video Games District 9

Though this might all sound rather cynical, Bruzzese maintains that this is not the kind of process that could be automated. "There is no algorithm that can predict art," he says firmly. In fact, one of the very first scripts that his team worked on was District 9, which was praised for its genre-bending take on the concept of an alien invasion. Arnold concurs, explaining that there is always an element of subjectivity when it comes to finding the best screenplays.

"In the past it's always been you start out with a script that either makes you laugh, cry, or feel some form of emotion. That was the base test for when we were reading scripts... you wanted to feel some kind of visceral, emotional connection either to the character or the storyline."

Though the oft-cited success of the critically-reviled Transformers movies may suggest that the overall quality of a film has little impact on its box office, Arnold says that, as a general rule, studios can't just "throw garbage up on the screen" and expect it to perform well, even if it does have a recognizable franchise name attached. A movie's ability to stick in its audience's mind will mark "the difference between whether they just break even or whether it explodes." With that said, some franchises can get away with a lot more than others.

Next: Why Twilight is a Safer Bet than Batman

Why Twilight is a Safer Bet than Batman

Edward and Bella dance together in Twilight: Breaking Dawn

The future landscape of the box office is filled with ever-expanding universes. There's Star Wars, with its array of sequels and spin-offs. There's the seemingly unstoppable tread of the MCU and its cocktail of sequels, team-ups and standalone superhero stories. There's Fox's ever-lucrative take on the X-Men. Then there's the looming presence of the DC Extended Universe, which will bring some superheroes to the big screen for the very first time.

It might be assumed that recognizable brands like Batman and Star Wars are the most surefire way to score a box office hit, regardless of quality, but actually the safer bet are franchises that are finite. That is to say, series like The Hunger Games, Harry Potter, Twilight, Divergent, The Lord of the Rings, and even Fifty Shades of Grey - adaptations of books that have defined beginning, middle and final entries. These films, Bruzzese explains, don't really need to blow audiences away, because fans of the source material will know what's coming anyway. "As long as you do a fairly good adaptation of the [Harry Potter] books," he explains. "You're going to be fine." But while there currently seems to be no doubt at all that Star Wars: The Force Awakens will blow the box office away this December, it doesn't mean that the Star Wars franchise is bulletproof:

"If you look at a franchise that has a continuously expanding universe - such as Star Wars, such as Batman or any of the Marvel [movies] - the moment it begins to falter, you only build up so much good will there... This happened with Star Trek. The Star Trek franchise, by the time it was done, every movie began to gross far less than the movie before. The whole franchise had to be completely rebooted, with almost an origin story and a different vision... So the franchises can certainly lose their narrative way - whether it's a horror franchise or science fiction or action adventure - unless it is a self-contained, finite franchise like Lord of the Rings or Harry Potter or Hunger Games."

Star Trek Beyond charity contest

It's little wonder, then, that so many young adult novel series have been adapted for the big screen, and why it's become a habit for the final entry to be split into two parts. If fans are going to show up to see them no matter what, then why not make the franchise last a little longer?

One aspect of revenue that can't be ignored is overseas performance. In the case of Pacific Rim, 75% of the total box office gross came from overseas ticket sales, with a third of that coming from China alone. Pacific Rim, however, is something of an exception to the rule, in the sense that it was an original film. The Guardian's box office analyst, Phil Hoad, says that in most cases the key to overseas success is - you guessed it - franchising.

"Often what you'll find is that first entries to franchises tend to gross more highly in the States... and then as you release the sequels, as people become more aware of them as the property becomes more established elsewhere, then that percentage [of international box office] will start to increase... I really think that franchising has grown up in tandem with the expansion in overseas box office... It's become really important to provide people with different viewpoints on life and different backgrounds with a common anchor for their filmgoing experience."

As studios grow ever more conscious of the need to make American films appeal to a global audience, there is also a growing conversation about what kind of people are being represented - or not represented - in those films. That brings us to the topic of what could the be most divisive aspect of Hollywood's movie-making habits.

Next: The 'D' Word

The 'D' Word

Christian Bale and Joel Edgerton in Exodus Gods and Kings

The idea of appealing to people of varying backgrounds and life experiences is an interesting one in light of the fervent discussions surrounding diversity in the film industry - a discussion that has attracted federal attention into Hollywood's hiring practices. The imbalance of male vs. female characters in mainstream films is so great that Dawn of the Planet of the Apes director Matt Reeves didn't realize until it was pointed out to him in an interview that there was almost nothing for female characters to do in his movie (Keri Russell was the only actress who was given lines, and there weren't many of them).

Race is another prominent issue; Insurgent actor Daniel Dae Kim told Screen Rant earlier this year how hard it is to find decent roles written for Asian-American actors, and director Ridley Scott quite bluntly said that he cast Christian Bale as Moses in Exodus: Gods and Kings because, "I can’t mount a film of this budget... and say that my lead actor is Mohammad so-and-so from such-and-such." More recently, Roland Emmerich cast Jeremy Irvine as a fictional "straight-acting" gay man to lead the charge in Stonewall, rather than making the movie about one of the transgender women of color who were known activists at the time. Emmerich's explanation for the decision was, "When you make gay films everybody says it’s for gay people, but no it’s not. The majority is straight."

These and many other examples create the impression that there is a rule in Hollywood - whether spoken or unspoken - that white male protagonists are 'safe' and anything else is a risk. Yet this mindset didn't seem to do Scott or Emmerich much good. Exodus: Gods and Kings grossed just $268 million worldwide on a $140 million production budget, while Stonewall hasn't even managed to break the $200,000 mark.

Hunger Games: Mockingjay - Part 2 IMAX poster and clip

Despite being fairly convinced that Hollywood's habit of making characters white and male by default is more superstition than pragmatism, I still brace myself for bad news when I ask Bruzzese if he's come across any pattern in how the demographics of a movie's characters affect its box office potential. After all, if audiences are so conditioned that they'll object to a horror movie where the band of killers has a motive, have they also become so used to seeing certain kinds of leads in movies that they'll object to anything else?

"Race is difficult to speak to. There's no phenomenon of Latino movies, very much, but there is one of black-centered movies... If you cast a lot of black actors or actresses in a film, you do have the possibility of recharacterizing that film for a black audience... You can actually change the tenor of the film by doing that.

"But in terms of gender I think it is one of the most unfortunate things is that so many films have characters that could be - and, narratively, should be - cast female, but because there is a mistaken belief in Hollywood that young males in particular draw box office - which they don't - and that young males will only go out to see male lead characters - which again, they won't - it causes so many of these scripts and narratives to be disproportionately male. Even the crowd scenes are disproportionately male...

"Every time a movie with a female lead does well at the box office - you have articles out there expressing all this surprise. And why it's surprising I have no idea, because every year there are plenty of movies with female leads that do extremely well at the box office. There's just this old school reluctance to it."

This mindset seems to be one that's changing very slowly, but it's encouraging to look at the posters for Star Wars: The Force Awakens - with John Boyega and Daisy Ridley as the new young leads and Oscar Isaac as Resistance pilot Poe Dameron - and see that Disney isn't afraid to take 'risks' with its biggest new franchise.

Star Wars: The Force Awakens - Finn (John Boyega) and Rey (Daisy Ridley)

The Princess Bride screenwriter William Goldman famously said that, in Hollywood, "Nobody knows anything... Not one person in the entire motion picture field knows for a certainty what's going to work." It's one of the things that makes the film industry so exciting to observe, and which no doubt makes it a terrifying place to work.

Though there are patterns and trends and techniques, there is ultimately no formula for box office success, and even if there was one it would probably have changed before anyone had time to decode it. With a global audience that's constantly developing new interests, demands, and ways of communicating, the best that studios can do is try to make good movies and pray that they'll hit the mark.