A good script, good pacing and an excellent supporting cast all help make this one of the best Monogram Chan films. The one weak link among the actors is the entirely underwhelming performance of the actor playing Eddie Chan, Number 4 son.A cranky inventor lives in an old mansion, waited on by the usual group of suspicious types who make good suspects! Chan is deft as always. You can almost sense him underplaying the humor of his scenes with Number 4 son, perhaps in an old pro's response to dealing with another actor who is just painfully bad. This was that actor's lone outing in a Chan picture--mercifully, for Chan fans. Even with him in it, this is still a very enjoyable film. The motto-spouting sheriff is a nice counterpart to Charlie. Anyone who has the idea that Monogram could not make a good Charlie Chan film, should see this movie. It's a winner. SPOILER ALERT: The body count in this film stands at five! I think that might be a record for any Chan movie!

Now how does all this go together? Well, there's scientist Harper who's working with his assistant Meeker on a gas formula that turns wood into coal instantly (and would be of enormous interest to any government during the War); he's turned a lonely old mansion into his laboratory, and he trusts nobody, so he keeps his formula locked in a secret chamber with a panel that closes automatically if anyone unauthorized enters and tries to take the envelope, and only HIS voice can open it again, while inside a deadly gas streams out to kill the invader...And since he trusts and likes nobody, when he's killed by a poisoned dart in his laboratory, ALL the household members are suspects, because nobody liked him, either... There's his colleague Meeker, his butler Roth, his sister Louise, his niece Jean, his assistant in his hobby, making puppets and toy robots, Stella, and mute chauffeur Michael - and if that weren't enough, a policeman disappears mysteriously near the house, and a little later Harper's alleged stepson Lloyd Archer turns up to claim the formula! So a LOT of difficult, and dangerous, detective work awaits Charlie Chan when he takes over the case; and inevitably, he's got to take his 'number 4 son' Edward and Birmingham with him to 'assist' him... The confusion continues, with a 'walking' corpse, the policeman's body being found in a closet, and mute Michael bringing Charlie an important piece of evidence: a jade mask, one of those hanging on all the walls, effigies of all the members of the household - but while handing it to him, Michael is also killed by a poisoned dart, and the mask is broken... So what is Charlie to make of all this?? A VERY intriguing crime puzzle, with the good old spooky settings of an old mansion, a big lot of suspense - and humor, as always provided by Birmingham and a Chan son; this time 'Edward', obviously the bookworm of the family, complete with glasses and scientific comments on everything - and played by Edwin Luke, the younger brother of Charlie's 'number one son Lee' from the Warner Oland films, Keye Luke!

This is my ninth review of a Charlie Chan movie in series chronological order on these consecutive days. In this one, a scientist working for the government is murdered in his house. As usual, Charlie rounds up the suspects there...Instead of his usual "No. 2 Son" Jimmy, Chan has "No. 4 Son" Eddie (or Edward as he prefers to be called) on board assisting him. He is played by Edwin Luke, younger brother of "No. 1 Son" Lee who was played by Keye Luke in the earlier Warner Oland entries. Unlike the other Chan sons, this one is not so bumbling since he wears glasses and is a bit intellectual though he's also not as charismatic. Good thing there's still Mantan Moreland's Birmingham Brown to provide the charms especially since his "scared stiff" stereotyped role is a little subdued though he does provide a quite funny ending due to that. Another funny comic relief character is provided by the slow talking Sheriff Mack who provides his own wisecracks when talking to Chan and is played by Alan Bridges who I just found out here is another player from my favorite movie, It's a Wonderful Life, as he played another sheriff that was supposed to arrest George Bailey. Anyway, I very much liked this Chan entry, even the reveal of the murderer at the end, so on that note, I highly recommend The Jade Mask.

One of the more creative Monogram Charlie Chan movies, The Jade Mask involves the murder of a scientist named Harper who developed a gas that can turn wood into a substance as tough as steel. Naturally this would be very useful for the government to have for the war effort (World War II that is). Harper's entire family become suspects and it is up to Charlie Chan, his number four son Eddie and Birmingham Brown to figure out who did it.The thing that sticks out most about this film is the fact that there is no jade mask, and no reference is ever made to a jade mask. Rather, Mr. Harper had plaster life masks made up of his family in order to be able to identify them should they ever try to steal from him. The masks do play a role in solving the crime.As with all the Monogram Charlie Chan's, the budget for this movie was very low, and the set where the film takes place is reused throughout many of the Monogram Charlie Chan films. The acting is not entirely the best either, Number Four Son is well below the quality of Number One Son, and is somewhere on par with Number One Daughter. Mantan Mooreland steals the show as usual. This is essentially a typical mid to late run Charlie Chan film. Entertaining, but of low quality.