Gaslight
A series of misunderstandings (like rat poison, pills, a shovel, and doctor's advice to ""get rid of the old thing"") causes a sick Fred to think that Cal is trying to kill him.
Other episodes for this season
A series of misunderstandings (like rat poison, pills, a shovel, and doctor's advice to ""get rid of the old thing"") causes a sick Fred to think that Cal is trying to kill him.