With assistance from new intern Mark, Gigaler.com employee Griffin records video interviews with company cofounders Tom and Chris. Tom and Chris explain their startup's goal of creating a predictive algorithm that curates custom video content for their homepage's visitors.An anonymous source sends Griffin a supposed snuff video of a blonde woman wearing white preparing to commit suicide in a cemetery. The video ends in a sudden jump scare when a loud scream accompanies a masked man lunging at the camera.Impressed at the effectiveness of the screamer video's scare, Tom, Chris, and other employees agree to post the video on their site. The content goes viral and boosts Gigaler's popularity.Griffin receives a second video. In it, the blonde woman is seen on a bed before the masked man suddenly appears for another screamer scare.Hoping to contact the creator in order to obtain exclusive content, Tom tasks programmer Abbi with tracing the video's source. Abbi traces the uploader to an address and phone number near Rochester, New York.Tom calls the number. A skittish woman who identifies herself as Tara hesitantly answers. Tara cryptically references a man named Francis in regards to who makes the videos, and implies that she is subservient to the unknown man. During a second phone call later, Tara continues to say that her association with Francis is complicated and he cannot find out she is talking to Tom.Comments posted to the videos indicate that the woman depicted resembles Tara Rogers, who went missing several years earlier. Concerned that they are connected to a crime, Tom calls Tara to confirm her identity. Tara abruptly tells Tom to not call her again before hanging up.Abbi identifies a tombstone in the first video as belonging to Francis Tumuelty, who was suspected of being Jack the Ripper. Based on this, Tom and the others conclude that they were the targets of a prank all along.Still hoping to turn the experience into content that will attract site traffic, Tom convinces Chris, Griffin, and Abbi to go to Rochester with him to film a video confrontation with Tara about the hoax. After visiting the Francis Tumblety tombstone, Tom surprises everyone with a nighttime stop at Tara's address. When no one responds to Tom's knocks, the quartet leaves.Tom, Chris, Griffin, and Abbi retire to the home of Abbi's friend Emma. The five of them share dinner and discuss Tara Rogers while also enjoying their evening together.The next day, Tom and Griffin return to Tara's address. Tom compels Griffin to go inside with him when he discovers the side door unlocked. Although the house appears dirty and deserted, Tom and Griffin find candles melted on a mantle and a pantry full of bloody jars.Upstairs the men find the bedroom depicted in the second screamer video. Tom's car alarm goes off outside. Tom leaves Griffin alone in the bedroom while he goes outside to his vehicle. Francis surprise attacks Griffin. When Tom returns, Francis attacks him too.Back at Emma's, Abbi shows Chris footage from the previous evening that shows someone was stalking them outside Tara's house. A text message from Tom's phone asks Chris and Abbi to come to Tara's address. Emma drives them.Inside the house, Abbi finds Tara curled up and crying in an upstairs bedroom. Francis suddenly attacks Chris, prompting Abbi and Emma to flee. Both women are separately chased and ultimately attacked by Francis.A new screamer video appears online with Abbi having replaced Tara as the woman in white in front of Francis' grave.