Boris Karloff plays an inventor of high-tech burglar alarm systems. Twenty years before he was ripped off by crooked Samuel S. Hinds, who took full credit for his invention and built a thriving security business out of it. Now Boris has invented a system to top his old one. He makes the boneheaded decision to trust Hinds again and is again ripped off. So he teams with small-time thief Petty Louie to break into places and make Hinds look bad, leaving behind notes signed Night Key. But then a gang of crooks kidnaps Karloff and forces him to help them commit real robberies.It's a mix of science fiction and crime picture. Karloff is excellent as always. I don't think I've ever seen a bad Boris Karloff picture. Petty Louie, played by Hobart Cavanaugh, is lots of fun. Samuel S. Hinds plays a villainous role very far removed from Peter Bailey. Alan Baxter and Ward Bond are the two most noteworthy gang members. Only drawback is the insipid romantic subplot between Karloff's daughter Jean Rogers and security guard Warren Hull, but it doesn't intrude on things too much. It's a fun movie Karloff fans will love.

Actor Lloyd Corrigan took a turn directing this little-seen but fun thriller that casts Boris Karloff as elderly inventor David Mallory, who has created a new state-of-the-art burglar alarm that former rival Steven Ranger(played by Samuel Hinds) has bought, but maliciously refuses to put on the market, ruining Mallory because he had married a woman that Ranger had loved. Furious, Mallory plans revenge by preventing the alarms going off in Ranger's stores during minor thefts, but this brings on the unwanted attention of gangsters, who kidnap Mallory's daughter Joan(played by Jean Rogers) to force him to work for them. Pretty good film has a sympathetic performance by Karloff and a good pace, with imaginative story. Deserves to be better known.

This is one of the oddest Boris Karloff films I have ever seen. I don't mean this in a bad way, but say this because the plot is so atypical of his films. Instead of a horror film, it's sort of like sci-fi and comedy combined! Now calling is 'sci-fi' might be problematic. The film looks like it was set in 1937 but the electronics shown in the film really weren't possible for the day--you just need to suspend disbelief and enjoy.The film begins with Karloff and his daughter excitedly talking about how much better their lives are about to become. It seems that Karloff is an electronics genius and has invented a super-advanced alarm system for businesses. Now he can afford the eye surgery he needs AND give his daughter everything she wants. However, Karloff is soon cheated out of his plans by an old business rival who did exactly the same thing years before--so you'd wonder why Karloff would agree to sell the same jerk this patent! Well, it's not totally unbelievable, as Karloff's lawyer secretly is working for the jerk!! When Karloff finds out the truth, he threatens to do bad things if they don't honor their agreement. The jerk laughs it off and so Karloff, who invented the original system to the company 20 years earlier, uses one of his inventions to break into the businesses with contracts with this monitoring service. But he doesn't steal anything, as he's basically a good man. Instead, he leaves silly messages that the system stinks and can easily be compromised--thus hurting the jerk's reputation. Karloff assumes that eventually the jerk will give in and honor his crooked contract.In the meantime, two things happen. First, the jerk refuses to budge at all--sending out his goons to harass and threaten Karloff's daughter. Second, real criminals find out about Karloff's device and kidnap him--trying to force him to work for evil. So what is Karloff to do--help the crooks or back off on his attack on the jerk? Well, there's a lot more to it than that and I won't ruin it by saying more.The bottom line is that the film has clever writing and despite a fantastic story, it was handled so well that you can't help but get sucked into the film. The great acting and breezy direction sure helped--making this one of the better B-films of the era.Exciting, clever and fun from start to finish.

David Mallory is an inventor. Twenty years ago, he invented an alarm system that was so good his partner, Steven Ranger, stole his ideas and set-up his own security/alarm firm without compensating Mallory. Well, Mallory has now developed two new inventions. The first is an improvement on his old system – an electronic beam that detects intruders. He intends to sell the improvement to Ranger. It' s not until his old buddy does him wrong a second time that Mallory unveils his second new invention – an electronic key that will allow anyone who uses it to bypass the Ranger security system. Mallory begins using it to set off alarms all over town as a joke to annoy Ranger. But when the local crime boss gets wind of Mallory's invention, he wants it – and not for practical jokes.While Boris Karloff is always welcome in any movie he appeared in, the role of David Mallory could, in all honesty, have been played by just about anyone. The role did not require Karloff's unique talents and abilities. I suppose that's one of the things that bothers me the most about Night Key – you have Karloff, why not use him to the fullest? I understand that Universal owed Karloff a movie, but why make this? Why not put him in something more in keeping with the image that Universal had already built up? It doesn't make much sense to me.Overall, however, Night Key is an enjoyable little b-type picture. The film is nicely paced with rarely a lull to loss interest. Director Lloyd Corrigan does a solid job in that area. And the 68 minute runtime doesn't hurt either. The acting is good. Other than Karloff, I was impressed with Jean Rogers as his daughter and Hobart Cavanaugh as his less than reputable new friend. Though it's often predictable, the plot is nonetheless engaging. While I could have done without the subplot involving the relationship between Rogers' characters and one of the Ranger security guards, I've got few complaints otherwise. Overall, Night Key is not a bad way to spend an evening.