A serial arsonist is on the loose and the authorities are all but helpless in the face of his fiery rampage. Retired firefighter Jim Hadley, outraged by the death of his best friend in one of the arsonist's fires, offers to help catch the maniac before anyone else gets hurt.
Movies about pyromaniacs are a fairly common staple for the action market, but The Last Alarm is the only one we've found whose firebug worships Vulcan and starts conflagrations as sacrifices to that ancient Roman god of flame. As portrayed by George Pembroke, the arsonist keeps a statuette of Vulcan at hand and laughs with mordant glee as he peers through pop-bottle eyeglasses at each new atrocity.
J. Farrell MacDonald should have obtained a patent on his role as the heroic old-timer, which he also played as a policeman, a railroad engineer, a tramp, a frontier sheriff, a factory bull-of-the-woods and a sea captain. Here he is as expert as ever - one of the dependables. Mary Gordon, soon to become the perennial Mrs. Hudson to Basil Rathbone's Sherlock Holmes, and Polly Ann Young offer good support as MacDonald's family. Warren Hull, who later portrayed the Spider, Mandrake the Magician and the Green Hornet so ably for the serial fans, is here as the juvenile lead. As for Pembroke, he lays it on thick, which is precisely what the part wants.