The European vacation is over when Darrin and Samantha pack up and are about to head home. Their departure is disrupted when Larry and Louise invites them to spend a weekend at the Duke of Whitset's hotel castle. It turns out that this hotel is hanuted by a ghost named Henry, who happens to be the Duke's ancestor. Harry is turned on by Samantha, and to get a little bit close to her, he possesses Darrin's body. When Harry (in Darrin's body) is shut down by Sam, he moves on to Louise! Samantha calls up a lady ghost to ward Harry off. Darrin gets his body back when Harry leaves it to be with the lady ghost. Now we can call it a day in Europe as the cast heads for home.