A group of college students is using their school lab for their experiment to prove that the
multiverse exists. After lots of failed attempts, they use the latest model of their device on a
bowl with a goldfish and discover there’s a recurring pattern of particles in the water.
It’s not enough to make contact yet, but they conclude they just need more water and leave for
the lake. While driving, they continue to check the computer screens and get excited when they
see flares. Gerry decides to speed up, and when they turn around a curve, they almost hit another
car. Thankfully Gerry moves his car out of the way just in time and stops it next to the hill,
but the other car isn’t so lucky and now it’s stuck on the edge of the cliff. The car’s wheels
keep on turning and they can hear the group inside panicking, so Loretta goes to check on them while
the others call for help. When she reaches the window, Loretta is very shocked by what she sees
inside the car. Then a hand reaches out and Loretta grabs it right before the car finally
falls down the cliff, killing everyone inside and Loretta too. Gerry and Amy have to hold Danny as
he has a breakdown over his dead girlfriend. Five months later, the team is testing a new device to
measure emotional reactions to different pictures. Gerry thinks they should get the full emotional
spectrum, but photographs of Loretta and a car put Danny in a really bad mood so he angrily takes off
the headset to leave. Then Gerry notices on the screen the reaction Danny had when Amy touched
him, and she confirms they’ve been seeing each other. Later at the library, Danny thinks he
sees Loretta behind the shelves. He rushes to go after her but follows the wrong woman,
only to see Loretta leaving through the main door. Danny tries to follow her again, but unfortunately
she’s already gone. In the evening, the friends go to a bar. Gerry admits he’s bored and misses the
old experiments because those pushed boundaries, so Danny has to remind him they stopped because
of a death. Suddenly Gerry gets distracted because he sees a girl that looks a lot like Loretta and
Danny rushes after her, but once again she’s gone. Then Danny goes to Amy’s house, apologizing for
thinking so much about Loretta. Amy wonders if he would like her more if she wasn’t deaf-mute,
but Danny assures her he likes her just the way she is and he’s just having trouble handling
his grief. That night, Amy has nightmares of someone drowning. The next day at the lab, Gerry
is shocked to find a second fish in the bowl. At that moment he gets a call from Loretta’s number,
and when he picks up, Loretta’s voice talks to him about the usual group activities. Angry,
Gerry says it’s a distasteful prank and hangs up. After class, Amy meets with Danny and they
share a kiss. Suddenly a woman slaps Amy: it’s Loretta, who is shocked to see her boyfriend is
cheating on her. Danny and Amy can’t believe what they’re seeing and take her to the lab,
where together with Gerry they explain she’s been dead for five months. Gerry theorizes she’s been
wandering around with amnesia, but Loretta assures them she’s been seeing them every day as usual
and that she never died or got hurt. Curiously, she doesn’t understand sign language anymore and
swears Amy has always talked to her. At that moment Loretta sees the second fish and gets
excited because she thinks it came from another dimension. She concludes this world’s Loretta is
indeed dead and she comes from another universe similar to this one but with small differences,
like Amy being able to talk and hear. Since in her universe she didn’t die, they never stopped
working on the experiment, so the machine on that side pushed her and the fish over. To prove it,
she pulls up her sleeve and shows them her new tattoo, explaining all four of them got the
same one recently. Afterward, Danny drops Amy at her home and apologizes for not staying together
tonight, explaining he needs to be there for Loretta. The rest of the ride is quite awkward,
and since Loretta can't go to her home because she’s supposed to be dead, Danny allows her to
stay with him but without sharing the bed. Danny ends up sleeping on the floor and when Loretta
tries to ask about Amy, he ignores her questions. Seconds later in their respective homes, Gerry,
Amy, and Danny begin feeling unbearable pain. They wiggle on the floor as thousands of voices echo
in their head, and after lots of screaming, the pain just stops. The next day Amy is upset to hear
Danny brought Loretta over, not knowing how to handle the situation. They go to the lab and find
a worried Gerry, who explains someone broke in and searched the place, leaving a mess behind and
a dead fish in the bowl. Amy and Gerry wonder if it was Loretta, but Danny immediately defends her.
When Loretta joins them with coffee, she notices that the dead fish is the one from the other
reality, and she worries about what it may mean for her own life. Later when Gerry returns home,
he finds the door of his house open and the alarm off. As he notices some abandoned food and beer,
Gerry hears a noise and rushes upstairs, where he sees his bedroom has been searched too. After
noticing there’s money missing, Gerry hears another noise and runs to the front door,
but the thief is gone and has dropped his science trophy nearby. Meanwhile Loretta decides to spend
the night in a motel. She decides to call her parents but doesn’t say a word, instead she hears
them yell at her for using their daughter’s number as a sick prank before hanging up. The next day,
Loretta goes to see Amy and makes an effort to use a few words in sign language as she offers a pact,
telling her about the motel and saying they both should stay just friends with Danny until they
figure out what’s going on. Amy agrees and the girls become best friends again. In the afternoon,
Gerry brings Danny to the janitor’s secret room to share a drink. While they discuss Loretta,
Danny accidentally drops the flask, and Gerry asks him about potential muscle weakness,
comparing it to the dead fish. Danny is confused by such a statement, so Gerry pulls up his sleeve
and reveals the same tattoo Loretta has, meaning he’s an alternate Gerry from her universe. To make
matters worse, Danny starts to feel sick because Gerry put something in his drink. Gerry begins
explaining Loretta opened a door to this world and now they’re all stuck here because there’s
no machine to send them back. One universe isn’t supposed to hold two identical versions of the
same mass because it goes against the laws of physics, that’s why a fish died and the
friends have been feeling unwell since last night: it’s time healing itself. Loretta is
fine because her local version is already dead. Gerry wants to keep the Danny from his own world,
so he walks behind this Danny and keeps him from breathing until he dies. Meanwhile the
Gerry and the Amy of this world notice their hands are shaking rather ominously. At a bar,
Loretta is chatting with the real Gerry when they’re suddenly interrupted by alternate Danny,
who greets Loretta with a kiss. She feels very uncomfortable by this and leaves, so Gerry calls
Danny out for behaving weirdly and mentions Amy, causing Danny to get offended by these
weird accusations and he leaves as well. When he gets to his car, Danny finds alternate Gerry,
who explains to him what’s going on because Danny hadn’t realized he’s crossed over until now. As
Danny freaks out, Gerry shows him his hand is shaking and asks him to kill the local Gerry for
him. Danny freaks out again and tells him to do it himself, but Gerry says he tried and wasn’t able
to. It turns out it was him who broke into Gerry’s house and grabbed the trophy as a weapon, but when
he saw his own face, he ran away. However Danny still refuses to do any killing and Gerry gets
furious as he yells, making Danny realize that Gerry is off his meds. Later in the afternoon,
alternate Gerry sneaks into the house again and steals a gun. At the motel, Loretta watches the
news coverage of her death, causing her to cry deeply. Meanwhile Amy visits Danny and tries
to kiss him, but he immediately pushes her away. Amy realizes this isn’t her Danny and runs away,
seeing her hands shake while she starts her scooter. Moments later, Amy comes home and
is very rude to her mother, who is also deaf-mute and can quickly tell her daughter is acting weird.
Amy ignores her preaching and rushes upstairs, where she notices the television doesn’t have
sound. As she looks around, she finds a school diploma for deaf people and a newspaper clip
about Loretta’s death, and she curses aloud. This is alternate Amy, who is finally realizing she’s
jumped into another reality. Freaking out, she calls Gerry to discuss what’s going on,
causing Gerry to also freak out when he hears her talk. Realizing this isn’t her Gerry, Amy quickly
hangs up. Then Gerry gets a text from his Amy, asking him to meet at the library. They exchange
information and realize all four friends have crossed into this world. Remembering the fish,
they start fearing for their lives. Meanwhile alternate Gerry is taking Loretta for a drive,
making her scared by going too fast. Eventually he stops the car in the middle of the road to
show her the tattoo and prove he’s her Gerry, so Loretta shakes his hand, agreeing to be partners.
She also notices his fingers are shaking, which reminds him of what he must do. On their way back,
Gerry drives even faster as he rambles like a maniac. Eventually Loretta gets off and refuses to
tell Gerry where she lives, pointing out he truly is losing it. In the meantime, real Gerry goes to
see Danny, demanding to know where his real friend is. Danny pushes him away and tells him that the
other Gerry killed him, pointing out that in his world Gerry always had a foot in the crazy bucket.
Back to Amy, she rushes back to her house and finds her mother sleeping. At that moment she gets
a text from Gerry, warning her that his alternate self is a killer. Then she starts going upstairs,
noticing the pain gets worse the closer she gets to her room. Amy finds her alternate self waiting
on the bed, which scares her. Alternate Amy explains her mother is also deaf-mute and the
odds of passing it down were 90%, so it seems she got lucky. When she was younger, she was ashamed
of her mother and it made her mad for not having “a normal family”, so Alternate Amy wasn't very
nice to her. However in this world she can see that her other mom and local Amy are very close,
and she refuses to ruin that, wanting at least one mother to be happy. Then Alternate Amy leaves,
and when real Amy comes down, her mother is confused because she’s seeing her again. Amy
tells her that hadn’t been her and it’s just a misunderstanding, promising her she’s the real
one and that she won’t abandon her. Afterward Amy follows her alternate self and finds her walking
into the ocean where it all started. Amy remembers her dream and tries to stop her, but Alternate Amy
thinks the ocean can take her back to her world and tells Amy to take care of her mom before
diving in. Little by little the water pushes her down until she disappears, and Amy has a breakdown
over seeing herself down, but she also notices her body isn't shaking anymore. Meanwhile Loretta
goes to see Danny to warn him about Gerry, only to see the tattoo and discover the truth. While
they text Amy in order to meet, Gerry goes home and finds his alternate self, who takes out the
gun. Real Gerry pushes him back as he grabs his hand to smash it against the dresser, triggering
a fight that causes them to fall to the floor. At that moment the other three arrive and see a Gerry
choking the other, so Loretta picks up the gun and asks them to stop, but she doesn’t know who
to shoot. Danny jumps in and checks Gerry’s arm, quickly finding the real one so Loretta can knock
out the other one by hitting him with the gun. Once real Gerry has caught some air, he furiously
jumps on his alternate self and starts beating him up with the trophy until he kills him. Afterward,
the group travels to a bog to get rid of the body. On their way back, they almost crash
against an oncoming car, and the sudden turn to dodge it causes their vehicle to end up on
the edge of the cliff. It turns out they’re the car that caused the accident from the beginning,
and now the original Loretta comes to check on them, getting shocked when she sees her own face.
Alternate Loretta reaches out to confirm this is real and the accident happens again with the car
going down, dropping the whole group and the other Loretta into their deaths. Suddenly the day resets
and the four friends are back at the university, getting ready to try the experiment again.