Life - Ryan Reynolds, Rebecca Ferguson and Ariyon Bakare

Science fiction is often at its most exciting when it's based on a real-life technology, and there are few technological marvels today that match the International Space Station. Built by five different space agencies, which together represent 15 different countries, the ISS was gradually constructed over time as individual modules were launched into space and added to the overall structure. This ambitious project began in 1998, and the ISS has now been continually occupied for more than 16 years by various crew members from around the world. The number of people who have visited or crewed the ISS is now in the hundreds.

Given how remarkable an undertaking it has been, it's surprising that the International Space Station hasn't been featured in more films. It played supporting roles in The Day After Tomorrow and Gravity, but new sci-fi thriller Life changes things up with a story set entirely inside (and, based on the trailer, occasionally outside) the ISS. Directed by Daniel Espinosa and scripted by Deadpool screenwriters Rhett Reese and Paul Wernick, Life follows a crew of six astronauts from around the world as they discover a single-celled organism on Mars - the first evidence of extraterrestrial life.

Who are these brave (and possibly doomed) souls? Here's a quick breakdown of who's-who in Life.

Rory Adams (Ryan Reynolds)

Ryan Reynolds as Rory Adams in Life

Life marks a reunion for Reynolds in more ways than one, as the actor starred in director Daniel Espinosa's 2012 crime thriller Safe House and, of course, is part of the core Deadpool family along with screenwriters Reese and Wernick. Producer Dana Goldberg told us that Espinosa sought out Reynolds for a role almost immediately, and joked that, "We all looked like geniuses because [it was] long before Deadpool came out."

Reynolds plays Rory Adams, an engineer whom who describes as "sort of a generalized mechanic." He's also charged with repairing and maintaining the ISS, and the trailer showed a scene in which Adams ventures outside the space station.

"My speciality is the space walk and the mechanical arm, which extends beyond the ISS and serves as a giant catcher's glove, basically. That's my sort of mission up here, is to operate those things... and to just fix crap that breaks."

The crap that breaks at one point includes the shower (a flourish added for the movie, since astronauts on the real ISS have to make do with sponge baths), and since Jake Gyllenhaal's character is present while Adams is fixing the shower, Reynolds refers to it as "our shower scene."

Miranda North (Rebecca Ferguson)

Life - Rebecca Ferguson as Miranda North

All of the astronauts wear either a grey suit of a brown suit, which Reynolds delineates by joking that grey suit means "dumdum" and a brown suit means "smart guy." Ferguson's character wears a brown suit. Miranda North is a scientist from the Center for Disease Control, and describes herself as "a giant condom," explaining:

"My job is basically to, whatever we find, to protect Earth from it and to protect it from us... I have to make sure firewalls are up. Everything is safe."

"Somebody bleeds, she screams, 'Close your mouths! Close your mouths!" Reynolds adds.

Ferguson made waves in 2015 with her performance as Ilsa Faust in Mission: Impossible - Rogue Nation, which was also produced by Skydance Media, so Life sees her working together once again with Rogue Nation's producers, and she is also expected to return for Mission: Impossible 6.

Katerina Golovkina (Olga Dihovichnaya)

Life - Katerina

One of the many complications of shooting a movie that's set on the USS is hair, since the lack of gravity means that anyone who lets down long hair will end up "looking like a troll doll," as producer Dana Goldberg describes it. While Ferguson's hair was kept in a tight bun, Olga Dihovichnaya went a step further and cut off almost all of her hair for the role of Katerina Golovkina, the commander of the ISS.

Dihovichnaya says that Katerina sees herself as the protector of her fellow astronauts, but as someone who also makes mistakes that "make the story more interesting." She recalls that what she found intriguing about the script for Life was it's exploration of the "common reflex" reaction to anything new, foreign, or strange. The trailer showed the ISS crew elated at having discovered life on Mars for the first time, but it looks like it won't be long before things go awry and that reflex reaction to attack and defend kicks in.

David Jordan (Jake Gyllenhaal)

Jake Gyllenhaal as David Jordan in Life
Jake Gyllenhaal in Life

Living in space can do some strange things to the human body, which is why the crew of the ISS need a doctor around. In Life, Jake Gyllenhaal plays the space station's doctor, David Jordan. "He's the bad guy," Gyllenhaal jokes. "No, I'm just kidding." During our visit to the set we saw a pivotal scene being filmed in which Jordan appears to lock Adams inside one of the modules - perhaps to contain the threat of the alien lifeform - so he may really end up taking on an antagonist role of sorts.

Gyllenhaal explains that the movie being set in zero gravity reflects the kind of terror that the characters experience as they are confronted with the unknown.

"There are numerous third and fourth dimensions in this movie that play psychologically with these things that we fear and then, being out of control in more ways than one. Not just physically in space. Yes, we have chase sequences and things like that, where we're trying to get towards something or away from something in the midst of not having our feet underneath us. But there's also the fact this being, this thing, is a very particular thing. It poses a psychological terror that I think creates it's own non-metaphoric non-gravity in our minds."

Sho Murakami (Hiroyuki Sanada)

Life - Hiroyuki Sanada

"It was very unique," Hiroyuki Sanada recalls when asked about first reading the script for Life. "We are discovering some strange creature on behalf of all human beings... It's all about the creature but I think it's a great human drama."

Muramaki is an "experienced astronaut" and this is not his first (or second, or even third) space mission. However, Sanada says that it may be his last mission, because while he is on the ISS his wife gives birth. This means that the parameters of his mission change, on a personal level, as Sanada says his character's new mission to to "go back to the earth safely and then spend time with the family."

Sanada's fellow cast members speak favorably about his mastery of zero gravity acting. "He's f--kng amazing," Gyllenhaal says. "He can stand on two toes."

Hugh Derry (Ariyon Bakare)

Life - Ariyon Bakare - Hugh Derry
Ariyon Bakare in Life

Along with Miranda North, Derry is part of the British presence onboard the ISS and his brown suit designates him as a scientist - specifically, a microbiologist. This means that when the single-celled organism is brought back from Mars it's Derry's job to examine it, and the trailer shows him excitedly announcing to his fellow crew members that they've successfully discovered life of Mars... shortly before he is attacked by the specimen.

"The black guy dies first," Bakare says, then laughs. "No, no, that's not true."

Recalling when he first read the script, Bakare says, "I had this visceral, immediate reaction to it." The movie sees each character in the ensemble reacting to the creature in a different way, and he offers a hint that "I have my own personal journey with it."

Next: Life Producer Says Moviegoers Are ‘Hungry’ For Original Sci-Fi