Honolulu detective Charlie Chan (Warner Oland) spends an eventful weekend at an English country estate in this fog-bound series entry. Young Neil Howard (Ray Milland) has been accused of murder, but family friend Geoffrey Howard (Alan Mowbray) expresses the hope that Chan will be able to locate the genuine killer. The weapons this time include a set of poison darts, while a series of cryptic notes provide vital clues to Chan and his Scotland Yard counterpart Sgt. Thacker (E.E. Clive), who insists upon calling the humble oriental sleuth "Mr. Chang" throughout the picture. Crucial to the plot's development is a fox hunt, predating a similar sequence in John Huston's The List of Adrian Messenger by nearly 30 years. At 79 minutes, Charlie Chan in London is the longest of Fox's Chan series -- unnecessarily so, since the identity of the "surprise killer" is obvious from reel one.
by Hal Erickson synopsis