Jack Lemmon, rising young man in the United States State Department hasn't a clue when he rents a room from Kim Novak who turns out to be a fellow American in London. He also doesn't know she's The Notorious Landlady whose husband has gone missing and Scotland Yard thinks she did him in.
Americans in the diplomatic corps are supposed to be scandal free, even more so back in 1962 so poor Lemmon doesn't know what he's walked into. But his supervisor Fred Astaire does and he wants him to leave. But Lionel Jeffries of Scotland Yard thinks he'd make one great unofficial undercover man. So in the spirit of the alliance that defeated Hitler, Astaire agrees.
Later on after a hilarious barbecue scene nearly burns Novak's place down and gets the State Department unwanted publicity, Astaire wants to transfer Lemmon to Tierra Del Fuego, but Novak actually comes up and charms him into letting him stay. So much so that Astaire now wants to play Sherlock Holmes and solve the case himself or at least be Watson to Lemmon's Holmes.
Jack and Kim make a lovely couple in danger, 25 years earlier I could have seen Cary Grant and Carole Lombard in their parts. But when you set out to make a stylish comedy, casting Fred Astaire is always a stroke of genius. Director Richard Quine even had the good sense to acquire Astaire's classic, A Foggy Day from the defunct RKO studio where he introduced it in Damsel In Distress to use as background music. It's used to great affect on one of those foggy London nights where both of them are trailing Novak.
In the last half hour their sleuthing pays off and a rather intricate mystery is solved. Lionel Jeffries makes a dogged and determined Inspector Lestrade like Scotland Yard man, who if truth be told is one of the sleazier members of that organization ever portrayed on screen.
The joint creative hands who wrote The Notorious Landlady were Blake Edwards and Larry Gelbart. Can't do better than that for style and wit.
