The Cornetto Trilogy is the informal name given to a collection of three movies: Shaun of the Dead, Hot Fuzz, and The World's End. All three were written by Edgar Wright and Simon Pegg, directed by Wright, and starred Pegg and Nick Frost in the leading roles. The main characters are hilarious and unforgettable. There are the slackers Shaun and Ed in Shaun of the Dead, big-city cop Nicholas Angel and bumbling constable Danny Butterman in Hot Fuzz, and estranged friends, Gary and Andy, together for one last pub crawl in The World's End.

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Where these movies really shine, though, is in their diverse cast of secondary characters. Roles like Mad Basil in The World's End or Pete in Shaun of the Dead appear at first to be there simply as a setup for a gag but, in fact, turn out to be a significant part of the plot.

Mary (Shaun Of The Dead)

Mary and Simon Pegg in Shaun of the Dead

Mary first appears onscreen during the opening montage. She is working at a supermarket checkout and wearing a vacant expression. (Mary's supermarket is called Landis, a reference to horror director, John Landis). The next time the audience sees her, she's in Shaun's garden and one of the undead.

Shaun was oblivious to zombies in the street when he popped out earlier, and assumes Mary is drunk. It soon becomes clear that she isn't human. Although she is trying to kill Shaun and Ed, there is also a sense of sadness in the way that Nicola Cunningham plays the role. It reminds the viewer that the people who become zombies are victims too. Mary is a great character because she introduces a real threat to Shaun and Ed in an identifiable way.

Sergeant Turner & Sergeant Turner (Hot Fuzz)

The two Turners in Hot Fuzz

The desk sergeant at Sandford police station appears to be a pretty changeable guy. When Nicholas Angel first meets him, he is affable and friendly. The next morning he is unkempt, grumpy, and barely speaks a word. His personality appears to switch back and forth throughout the movie.

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It is only near the end that it is revealed to Sergeant Angel (and the audience) that there are, in fact, two Sergeant Turners. They are a pair of identical twin brothers, both played by comedian Bill Bailey. Both brothers are hilarious in their own way. The confusing situation around the identical twins – which nobody had bothered to explain to Sergeant Angel – encapsulates perfectly the weirdness of the small-town police station.

Guy Shepherd (The World's End)

Pierce Brosnan turning into an alien in The World's End

Former James Bond, Pierce Brosnan, has a small but significant role in The World's End. He is Gary King's old English teacher and appears in a flashback, smoking cigarettes with his student and sharing a joke. His cool demeanor shows why he was Gary's favorite schoolteacher.

When Gary and his friends next meet Shepherd, it is under much more sinister circumstances. Shepherd is now a "Blank," who tells them that the invaders are like benevolent teachers to persuade them to join the Network’s legion. Brosnan’s character cleverly demonstrates why the clones are so terrifying. Shepherd looks and sounds like someone who Gary once respected, but is now something malevolent. He changes from mentor to monster in the blink of an eye.

John (Shaun Of The Dead)

John in Shaun of the Dead as a zombie

John runs The Winchester, Shaun and Ed's favorite pub in Shaun of the Dead, where most of the movie is based. John is named after the landlord of Simon Pegg and Nick Frost's own local pub, "The Shepherds," located in Highgate, London, according to Moviemaker.com. Ed tells Shaun that John worked for the Mafia and the rifle behind the bar is fully loaded.

The audience never finds out whether Ed was telling the truth about John's Mafia connections, but, as it turns out that the gun was fully loaded, as Ed said, it is possible that he might have been. Steve Emerson portrays John as a dodgy-looking character who perfectly suits the seedy atmosphere of The Winchester.

The Andes (Hot Fuzz)

Wainwright and Cartwright talking to Angel in Hot Fuzz

When DS Wainwright (Paddy Considine) and DC Cartwright (Rafe Spall) are introduced by Inspector Butterman, he calls them "The Andes." It's a weak joke, and when he asks Sergeant Angel if he is wondering why they call them that, Angel responds straight away: "Because they're both called Andrew?"

Like most of the police officer characters in Hot Fuzz, Wainwright and Cartwright are oblivious to the horrors going on in Sandford. They're dismissive towards Sergeant Angel, saying that if he wants to be a big cop in a small town, he should go to the model village. The pair look as though they should be in a 1970s TV cop show, contrasting with Sergeant Angel's 21st century policing methods.

The Reverend Green (The World's End)

Trevor or Reverend Green in Hot Fuzz in two side by side images

The Reverend Green, played by Michael Smiley, is a small-time drug dealer. He is one of the few people in Newton Haven who hasn't been replicated. Gary tells him that the town has been taken over by "robots full of blue stuff." Reverend Green says robot means "slave" and "believe me. They are not slaves."

He leaves the pub after receiving an ominous telephone call, and the next time he appears at the confrontation in The World's End pub, he has become a Blank. Smiley portrays Green as a shady and ambiguous character. The audience is unsure what to make of him, which only adds to the movie’s atmosphere of increasing horror.

Pete (Shaun Of The Dead)

Pete with dead zombie eyes in Shaun of the Dead

Shaun's housemate, Pete (played by Peter Serafinowicz), has grown up and put his wild days behind him. When he is woken by Shaun and Ed playing loud music in the early hours of the morning, he flies into a rage. Ed mutters after his departure, "The next time I see him, he's dead."

The next time Peter appears, he is, indeed, dead. Or, more accurately, undead. There's a fake jump scare at the beginning of the movie when still-human Pete suddenly appears in the bathroom cabinet mirror, but he just wants to complain to Shaun about Ed. When Shaun encounters Pete in the bathroom a second time, the scares are a lot more real.

Aaron A Aaronson (Hot Fuzz)

Aaron A Aaronson in Hot Fuzz

After solicitor Martin Blower's murder, Sergeant Angel asks the station's detectives to speak to his clients. They reply that Blower represented most of the village. "Do you want us to go through the phone book?" "We'll put in a call to Aaron A. Aaronson, shall we?"

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At the end of the movie, during the fight in the model village, a young boy (Alexander King) is caught up in the action. He is a significant character because while Skinner uses him as a human shield, Angel instinctively tries to protect him from danger. The boy’s name is Aaron A. Aaronson, so maybe the Andes weren't being as sarcastic as they first appeared.

Basil (The World's End)

Basil in World's End sipping on a pint with a straw

Basil is a crazy old guy who props up the bar in The Famous Cock. The gang used to spend time chatting to him when they were younger, especially Steven, who formed an unlikely friendship with the old man. Basil is a conspiracy theorist who tells Steven about UFOs, lizard people, and underwater Nazis. He believes that the Bermuda Triangle was really two isosceles triangles forming a rhombus.

This made him better prepared for an alien invasion than the rest of the residents of Newton Haven. One of the last remaining humans, he drinks beer through a curly straw so The Network can't obtain his DNA to clone him. As Basil says, "Not so crazy now!"

Yvonne (Shaun Of The Dead)

Yvonne and her friends in Shaun of the Dead

Yvonne (Jessica Hynes) is an old friend of Shaun's. They run into one another the day before Z-day. Like Pete, Yvonne has grown up since their days together at university and has just bought a house. It is an uncomfortable moment for Shaun, as it highlights how little he is progressing in his life.

At the end of the movie, as Shaun and Liz - the only survivors - head towards the rescue helicopter, and Yvonne is there to help. Her conversation with Shaun echoes their earlier one: "Shaun, how's it going?" "Surviving." "I'm glad someone made it." Except that this time, they're not talking about life after university -- they're talking about surviving a zombie apocalypse.

NEXT: 10 Best Characters in The Cornetto Trilogy, Ranked