Lucifer (guest star Mark Pellegrino) drives Sam (Jared Padalecki) to the breaking point and Sam ends up in a mental hospital. Desperate to save his brother, Dean (Jensen Ackles) calls every hunter he knows for help. One of the hunters gives him the name of a healer who turns out to have a very familiar face (guest star Misha Collins). Robert Singer directed the episode written by Sera Gamble (#717).