The Signal's ending was literally out of this world - here's the alien test city explained. The Signal is a 2014 sci-fi thriller starring Brenton Thwaites and Laurence Fishburne (Hannibal). The story revolves around three MIT students who try to track down a rival hacker, only to end up in a mysterious facility run by Dr. Damon (Fishburne). Apparently, the three students have been exposed to a signal of extraterrestrial origin, but it's up to main character Nic to figure out the truth behind the signal and why he's being held.
The Signal is a low-budget sci-fi movie that features some great performances, an emotional story, and a shocking twist ending. The entire story builds towards the final reveal, and it's satisfying to rewatch the movie and see all the clues that were seeded throughout. Despite the modest budget, The Signal also features some impressive visuals and special effects.
Most of The Signal plays out like a mystery, with Nic eventually coming to believe he's being held in Area 51. His logic is backed once he realizes his legs have been amputated and replaced with artificial limbs made of alien technology. Nic eventually breaks himself and his girlfriend Haley, played by Ready Player One's Olivia Cooke, out of the facility using his new powers. The pair are chased across the desert and encounter a number of strange characters in the outside world, but the final scene finds Nic cornered by Damon and his men on a road. Haley is taken away and a furious Nic uses his new alien limbs to run right past Damon's roadblock - only to smash through a glass barrier.
The final moments of The Signal find Nic in a strange, warehouse-style area, and he looks back to see Damon remove his hazmat helmet to reveal he's some kind of alien wearing a human face. Nic then looks outside the window in front of him to see he's in outer space, realizing he was abducted by aliens for the purpose of integrating human beings will with their technology. The final shot reveals he's inside an alien test city, built to look like Earth, which is part of a larger spaceship.
The Signal's twist recalls 1998's Dark City, which featured a similar premise involving aliens constructing a city to use as a test environment for human beings. Some critics found the reveal too abrupt and reminiscent of The Twilight Zone, but in hindsight, the story was building towards this reveal the whole time and uses the concept to flesh out its themes of emotion overcoming logic. The movie also regularly pulls the rug out from viewers, so it only makes sense to end on the biggest rug pull of all.