After admitting to Sam that she can see ghosts, Melinda sets out to eliminate his skepticism by having him tag along on one of her cases. Unfortunately, the first ghost she encounters is a complicated and potentially dangerous one, Greer, who is attached to the school building that Sam is renovating. The building is actually an old psychiatric hospital, and Greer had died there after undergoing experimental electro-shock therapy procedures back in the 1950s. Worried that the school children will be victims of the same fate, Greer kidnaps the children in an attempt to protect them from the doctor she holds responsible, Dr. Byrd. After the children are found unharmed, Melinda and Eli try to convince Greer that the children are safe from Dr. Byrd, and that she should cross over. However, further investigation leads the gang to the discovery that Dr. Byrd was actually a ghost himself when Greer first encountered him, and that he had been able to communicate with Greer while she was experiencing electro-shock therapy, which suppresses the logical part of the brain that tells an adult they can't see ghosts. It turns out that Dr. Byrd had gathered a cult of ghost patients around himself, who he convinced not to cross over by playing on their fear of the light. Melinda and Eli then help these ghost patients, including Greer, cross over, convincing them that only love, not judgment, exists in the light. Meanwhile, the entire ghost whispering experience proves to be too much for Sam, and he and Melinda break up.