Set amid the Covid-19 lockdown, the film opens with a college student, Jessica (Jess), talking with a friend on her phone when a mysterious figure ambushes her and drags her into the darkness. A chilling news report later confirms her murder and reveals that the killer is still on the loose, setting a grim tone for what follows.
From there, the narrative largely unfolds through a laptop screen as a group of college friends converges on a video conference call. Katy organizes a birthday surprise for her best friend Sam, and the online gathering welcomes a tight-knit circle—Adam, Jacob, Sam, Brian, Becca, and Annie—as they prepare to celebrate remotely in a world kept apart by isolation.
Initially, the mood is light and playful. The friends shout “Surprise” and Sam expresses gratitude for the online party, explaining she’s supposed to be staying at her parents’ house for the moment. Yet the moment Sam steps away to take care of something off-screen, the atmosphere shifts. The background on her fake backdrop is exposed as deceit, and a creeping unease settles in as her friends realize she has been lying about her whereabouts. The tension grows when Jacob decides to check on Sam in person, joining the chat from his phone to show everyone what’s happening as he heads over to her house.
What begins as a routine visit quickly spirals into danger. Jacob enters Sam’s home and is suddenly attacked, only to reveal it as a staged prank before the screen stutters and his phone falls. The group’s fear escalates when Jacob’s phone continues to record without responding, and Becca—Becca—races to Sam’s place to check on her friend. Becca’s investigation leads her into Sam’s house, where she hides in the bathtub as a terrifying intruder moves through the home, eventually turning on the faucet and cutting off the video feed as her phone shorts out.
The members of the group struggle to process what they’re witnessing. Some suspect a prank, others fear a more sinister trap. When Robert joins the chat to wish Sam a happy birthday, his arrival heightens the suspicion that someone in the circle is orchestrating the disappearances. He leaves in frustration, but not before sharing his location data to prove he is not involved. The confusion becomes sharper when Annie, fed up with the chaos, decides to go to Sam’s house to look for her friend herself. She finds the computer Sam used for the video chat—the center of their digital world—and, despite the chatter among the others, mutters out a plan to investigate. In a tense moment, she removes Sam’s fake background, revealing the unknown assailant behind the screen. The others try to warn Annie, but the attacker strikes her down and she is knocked unconscious.
With Annie incapacitated, the group turns to the digital trail left behind. Katy discovers a number in Annie’s messages that doesn’t belong to their circle and passes it to Brian. Brian digs into the number and traces it to Justin Anderson, a man from Sam’s recent photos who seems to have a connection to her. Meanwhile, the trail of clues suggests that Sam’s relationship with Justin may be at the heart of the mystery. As the group delves deeper, they uncover a disturbing pattern: Sam had been dating Justin, and one of the photos Justin sent matches the killer’s outfit on the night of the crime.
The tension peaks when Jacob and Becca reappear—conscious but trapped in a closet somewhere—while Sam remains missing. Adam heads out to find Sam, and the others piece together a plan to locate Justin’s home using the photos and online clues. They track down his address and rally to rescue Sam, guiding Adam as he breaches Justin’s house and frees Sam, who is alive but frightened. The trio races back toward Sam’s house, keeping their video chat alive as a lifeline.
Katy finally reaches Sam’s house and locates the closet where Jacob, Becca, and Annie were kept. She frees them and makes a dash for the exit, but Justin arrives and locks the door, leaving Katy to face him alone. The rest of the group watches, unable to break down the door, as the peril becomes intensely personal. Katy confronts Justin, accusing him of luring Jessica from a dating app and attempting the same trap on Sam. Justin does not deny the accusation, and a frantic scuffle ensues. As the battery on Katy’s laptop dies, the screen cuts to black, leaving her fate and the outcome of the confrontation uncertain.
Some time later, the friends regain contact and they share news that Katy has survived the ordeal. A later news clip confirms Justin’s arrest for Jessica’s murder and for kidnapping Sam and the others. In a quiet, somber epilogue, Sam is shown on another video chat with Katy by her side, and the friends eagerly wish her a belated birthday. They open the present together, and as Sam looks toward the camera, Katy’s gaze lingers on the screen—an unspoken reminder of the danger they faced and the resilience that carried them through. The screen fades to black as their support network remains intact, transformed by the harrowing events they endured together.
