Chrissy gets a job typing out an X-rated diary for a client. Things get complicated when Mr. Roper sneaks a peek and assumes that the diary is about Chrissy and her secret lust for the "older man downstairs".
Mr. Roper is not getting along with his best friend Jerry. Jack, Janet, Chrissy, and Jerry all get the wrong idea when Mrs. Roper asks to use their apartment to talk to Jerry privately.
Jack takes Janet's visiting sister around town but Janet gets angry when he accidentally slips into bed with her in the middle of the night in a sleepy error.
When Mr. Roper alludes to a big surprise that he is going to have for Mrs. Roper on their anniversary, the roommates think that he is going to leave her for another woman.