Betrayal at the House on the Hill is the tenth and final episode of the first season of the YouTube Red series Escape the Night.
The guests discover they have been betrayed by Arthur the Butler, a former confidence man, and must unravel clues while being hunted by him and the house staff.
Months before the Guests Arrive
Arthur narrates his flashback with his wife, explaining that he is a confidence man, his current mark being his wealthy socialite wife. He is pouring tea, and he secretly poisons hers, serving her the deadly draught as he smiles and wishes her a happy anniversary with a toast. With one sip, she cries out in pain, succumbing to the laced tea as Arthur pulls off his wedding band, flipping it onto her corpse. He walked over to the window of their bedroom, contemplating his next job, when he receives a call from someone (presumably the Demon controlling the Mansion). He arrives at the mansion, intent on not only owning the cursed residence, but controlling the evil within.
The surviving Guests were captured by the house staff, terrified as to what has befallen them in the past 9 hours, as Arthur finally unveils his grand scheme: he needed the artifacts, as well as the previous owners gone, in order to control the house. As he gloated, he dropped the diagram for the true ritual, the one that the guests performed during 'Did Someone Call For An Exorcist?' being the wrong one. The staff then proceeded to chloroform the guests, and place them in the Torture Room, which was hidden inside the Butler's Chambers. Joey was the first to wake up from his drugged condition, followed by Eva and Oli. Joey was the first to notice an ornate wood box next to him, as well as a 'V' shaped poker, but the key did not fit the lock on his box. Oli tried using Joey's key on his chest, then passed the poker to Eva, who was able to open her chest and start to free herself from her chains, all the while being shouted at by a man who has clearly gone insane shouted nonsense at them.
Once they were all freed, they opened one last lockbox, which contained a note, presumed to be from Arthur, as well as his pocket watch. The note stated that by sunrise at 6:00, if they did not leave the house, the serum that was injected with would make them complacent and turn them into servants in the house. They escape into the Butler's Chambers, which contained not only the key to escape the room, but also Arthur's police file and the first clue to the last puzzle. Taking the clue to the first step of the puzzle, as well as the diagram to the ritual, Joey led the way out to the Manor grounds, their escape triggering an alarm that alerted Arthur and his accomplices.
Arthur, Marvin, and Sarah split up to chase the guests: Sarah patrolled the house, Marvin guarded the sides of the house, while Arthur guarded the back. The guests had to remain out of sight to stay safe, because if they were caught, they were dead. They made their way to the pool to look for the next clue to their puzzle, but Oli remembered where another reflecting pool was: the fountain at the front of the house. The Guests evaded Arthur and Marvin to not only secure the chest hidden in the fountain, but also three diamonds, which fit in the chest. When they opened the chest, they recieved two rubies, and the clue told them to look for a winged guardian protecting the second floor of the house that overlooked the front yard. After discussing briefly, they knew they had to get up to the second floor and to the gargoyle, avoiding Sarah in the process. After a few miscommunication errors and several harrowing escapes, they got to the gargoyle and inserted the rubies into his "eyes", unlocking the box for their next clue, and the emerald for the offering. They were directed to walk up a "spiral of pain" in order to feed a demon who "bathed in a pool of blood". Deducing they had to get to the spiral staircase in the back of the house, the Guests once again evaded capture, though Eva was nearly caught, but they retrieved the key to the brother's cell, returning to the wine cellar to free him.
Arthur's brother was hungry for revenge, as he was the final owner of the house to be freed, and went on a killing spree to free the Guests of the horrific game Arthur forced them to play. Sarah was the first to fall by his hook, followed by Marvin in gruesome fashion. Arthur was able to wound his brother, but ultimately fell as well. With revenge done, Arthur's brother scared the guests back into the house to perform the ritual and finally escape the nightmare. As Eva and Oli grabbed the artifacts and the sand, Joey spotted the deed to the Manor, pocketing it so the house would not fall into the wrong hands. They quickly drew the circle, Joey in the center to bind the fourth artifact, Oli reading the spell. The ritual was a success, banishing the evil, but the Guests had to move quickly, as they only had 5 minutes to bury the artifacts and leave. With their objectives finally complete, the surviving Guests departed the house.
The title of this episode is in reference to Betrayal at the House on the Hill, a cooperative board game published by Avalon Hill. Players explore a haunted house, not knowing who is the traitor until halfway through the game.