- Hugh Laurie (Gregory House)
- Robert Sean Leonard (James Wilson)
- Omar Epps (Eric Foreman)
- Jesse Spencer (Robert Chase)
- Odette Annable (Jessica Adams)
- Peter Jacobson (Chris Taub)
- Lo Mutuc (Chi Park)
Episode: Joy
Air Date: 2008-10-28
Runtime: 44 min
An ailing man suffers from blackouts and sleepwalks, leading the team to wonder if his sleepwalking is a symptom, or how the man is becoming exposed to something else. When the man's daughter grows ill as well, the team must provide a diagnosis before both die. Meanwhile, Cuddy adopts a newborn but when the birth mother displays a rash, she has to make a decision between putting the mother or daughter at risk.