Summaries

Synopsis

Eight friends reunite at a dinner party one night in California when a comet passes. Kevin asks Emily if she wants to come with him on his business trip to Vietnam, and she doesn't say yes. Kevin's ex-girlfriend Laurie is also at the dinner, and she wants him back. A power outage occurs. The hosts have some glow sticks that they use for light, and they decide to use the blue glow sticks. Everyone goes outside and sees one house up the street that still has power. When they go back inside, a glass is broken, which they didn't notice before. Hugh and Amir go to the other house to ask to use their phone, and a few minutes later they come back with a box. Inside they find a ping-pong paddle and pictures of themselves, including one that was taken that night, with numbers written on the back. Hugh says that at the other house he saw a dinner party set for eight people.The friends realize the other house is an alternate of theirs. On a notepad, Emily writes down the numbers from the box, looking for a pattern, but they can't find one.

They begin to write a note for the other house. A man approaches the house freaking them out but he quickly leaves, they find the same note that they have written already pinned onto their door. Emily, Kevin, Mike, and Laurie decide to go to the other house to see what's happening. While there, they encounter what appear to be copies of themselves carrying red glow sticks, and both groups flee back to their own homes.

Emily's group explains to the others that they met copies of themselves, except the copies were wearing red glow sticks instead of their blue glow sticks. Hugh goes to his car and gets notes from a physics lecture. After reading those notes, they deduce that the comet has created a split reality, and that one of the realities will collapse when the comet passes. The group argues about how to deal with the other house. Mike hysterically plots to kill their doubles before the doubles can kill them. They consider stealing the physics notes from the other Hugh's car to hinder the other reality from getting the same knowledge as them. But Mike decides to blackmail the other house's Mike, to prevent them from getting the lecture notes.

It's revealed that Hugh and Amir are from the house with red glow sticks. They take the box and go back to the other house, then the Hugh and Amir with blue glow sticks return. They explain that they found two notes at the other house too. They realize that there are more than just two realities, and they switch from one house to another when they go outside and walk through a dark area. Beth is then wrongly accused of lacing the food with some ketamine that she brought.

Outside, they hear someone smash Hugh's car window, and they go out to investigate. While outside, Emily has a sweet conversation with her boyfriend, before realizing she's talking to a Kevin from a different reality, then she goes back inside. The group decides to put a random marker in front of their house. As the marker, they leave a random object and photos of themselves in a box, and on the back they write down the numbers they get from rolling dice. They check how their new numbers compare to the numbers from the other house's box, which they wrote on the notepad earlier. Emily realizes that the numbers written on this notepad aren't the same numbers she wrote on the notepad earlier. When she asks other people, she finds that Lee and Beth are the only ones whose memory matches what's written on the notepad, because they're the only ones who haven't left the house since they wrote the numbers on the notepad. Kevin and Laurie are the only ones whose memory matches Emily's memory, since they're the only ones who have traveled with her the whole time. Hugh and Amir remember a third set of numbers, since they switched realities when they switched to the red glow stick house and again when they switched to the current house. Mike remembers a fourth set of numbers, since he switched realities when he went to blackmail himself.

The situation deteriorates further when a blackmail note arrives. Mike mentions that if there's a dark version of their group, maybe it's them. Another Mike arrives to try to kill them, scaring Laurie, who is comforted by Kevin. Emily leaves the house, and looks through several different houses, finding several where things are even worse.

Finally, she finds a reality where no one seems aware of the split and there is a happy Emily. In this reality, Emily had agreed to go to Vietnam with Kevin at the beginning of the evening, and their relationship had stayed strong. She plans to replace this reality's Emily. She destroys a car window to lure the group outside, then ambushes her double with ketamine. Her double is able to crawl back inside, forcing Emily to subdue her again in a bathtub. She then heads to the living room and faints. She wakes the next morning unable to find her double, yet everything seems fine. She searches outside and runs into Kevin. His cell phone rings, noting the call is curiously coming from Emily's number. While listening to the caller, he stares at her suspiciously.