When Frasier and Niles discover a skull while visiting their childhood home, the brothers use their deductive powers to unravel what they imagine to be a sinister murder.
The family tries to give Frankie a day to herself for Mother's Day as the perfect gift, but things don't go as planned.
Mac forms a bond with a student who is found wandering the streets covered in blood and wielding an axe.
Earl discovers that Joy has continued a holiday scam they started years earlier, and she has expanded the hoax to include her friends.
The team thinks animal rights activists may have been involved in the death of a professor at a university research lab.