Mr. Ropers' niece Karen (a lovely Christina Hart) comes for a visit, and Mrs. Roper doesn't think that he's showing her a good enough time. So Roper gets the bright idea to have Jack take her out, thinking that she'll be safe with him. Jack is resistant to the idea, until he sees what the young woman looks like. Frustrated with Jacks' lack of amorous attention, however, Karen ends up pretty much throwing herself at him. When Roper catches them kissing, he automatically throws Jack out of the apartment.
Here, we get more of an idea of what a shameless horn dog Jack can be, with Janet quipping that "his head was born on a swivel". Roper gets in plenty of comments on the nature of "people like Jack". Janet & Chrissy feel some resentment over Jack missing Janets' birthday party, but this also leads to a fairly frank conversation over how they would react to Jack if he weren't living with them. Jack, of course, ultimately proves that at heart he really is a good guy when he uses the money Roper gives him for an unexpected purchase.
While not quite as uproarious as this show could get, this is a very good episode with some great lines. Some of the best moments happen when Jack decides to have some fun with the small-minded, old-fashioned Roper and deliberately freak him out. Norman Fell is priceless during these moments.
Overall, a good episode.
Eight out of 10.