In the countryside of Ukraine lies a castle called Pidhirtsi. Dr. Vita Susak wants to turn the erstwhile tuberculosis hospital and Nazi experiment grounds into a museum, but she's concerned about the paranormal activity there. When GHI arrives, they begin by investigating tales of the nobleman who lived there who allegedly immured his wife because she was unable to have children. Visitors have spoken of seeing a White Lady - thought to be the nobleman's wife - and while Susan looks for her, she's hit by a dizzy spell, hears someone say "Oi," and feels something touch her face. While Britt and Joe seek the White Lady in the chapel, they also feel lightheaded. In an EVP session, they ask for a knock, and get one. They ask again, and again get a positive response.
Paul and Kris present their findings to Dr. Susak, who tells them that "Oi" is a Ukrainian expression of surprise. They show her a photo taken while Susan was having these disturbing experiences that captured a large shadow hovering near Susan's face. Next, they tell Dr. Susak of the loud knocks captured by Joe and Britt, and the garbled speech they caught on an audio recorder. Certainly, there is paranormal activity afoot, and Dr. Susak feels that the spirits are ready to communicate and respectful of the investigation.
The crew is needed next in Poland, where stories of a woman accused of witchcraft hound a hotel in the town of Reszel. The woman, named Barbara Zdunk and called "Poland's last witch," was held in a dungeon in the hotel - formerly a castle - and raped multiple times, bearing two children from the assaults. Visitors are haunted by screams, which they believe are Barbara's, crying out for her innocence.
An intriguing tale is that of two men in the billiards room (formerly the dungeon where Barbara was held). One man was losing, and playfully called, "Help me, Barbara!" Immediately, the balls began to move. Barry and Kris attempt to recreate that night, and after a moment of stillness, Barry jumps: Something touched his leg. They hear banging, but can't find the source.
Susan and Paul, investigating claims of a cold spot in the bar, begin to feel the chill for themselves. Susan sets out a drink for the spirits, and the ice moves and the straw spins in the glass.
In analysis, they discover that this movement was just the normal settling of ice as it melts, and Paul is seriously disappointed that he didn't see the kind of paranormal evidence he had thought. Paul and Britt, however, caught what could be heavy breathing while investigating in the castle's tower. They present this to the owner, telling him that there may be activity, but he has nothing to fear.