S4, E7: In ""The Invisible Woman"" Harriet Winkler wishes to become invisible so she can spy on her philandering fiancee and finds that the one thing their relationship doesn't have is trust. And in ""The Snowbird"" Ned Pringle falls in love with one of the Flying Ferinis', a trapeze act, and in order for him to get close to her he takes on the challenge to become a trapeze artist himself.