In the present curious MGM feature, Lorre plays an eccentric surgeon known for dramatic cures in hopeless situations. He develops a crush on beautiful Frances Drake, an actress featured in a play he attends every night. Lorre pays Drake a backstage call, during which he creeps her out considerably. Lorre is agitated to learn that Drake is married to concert pianist Colin Clive.
As bad luck would have it, Clive is involved in a train wreck that mangles his hands. Aware of Lorre's professional reputation, Drake begs Lorre to save Clive's hands and career. Desperate to impress his would-be love goddess, Lorre performs a hands transplant on Clive, using the cadaver of executed knife-throwing murderer Edward Brophy.
Predictably, Clive's new hands soon take on a life of their own, compelling him to kill. Victim number one is Clive's stepfather Ian Wolfe, a thoroughly unpleasant man who refuses to lend Clive money. But Lorre is the real murderer, whose motive is to separate Clive from Drake so that he can have her for his increasingly maniacal self.
Supporting roles are played by Sara Haden, Drake's jolly middle-aged maid; May Beatty, Lorre's weird parrot-loving housekeeper; and Ted Healy, a persistent reporter who gets revenge on the publicity-adverse Lorre by siccing the police on him.
How I felt about it. Karl Freund was presumably selected as director because of his success with The Mummy (1932). It was his last screen credit as director, but his lengthy career as a cinematographer continued through "I Love Lucy" in 1956. The actual cameraman for Mad Love was the legendary Gregg Toland.
It was probably Freund's decision, though, to replace close-up shots of Frances Drake's wax dummy with those of Drake herself, wide-eyed and motionless. This creates the odd effect of making the dummy appear to be a zombie awaiting orders from her Svengali, Peter Lorre. Instead, her physical replacement of the dummy provides the plot device for Lorre's downfall, which is inevitable due to the Production Code, rigorously enforced since the year before.
Another interesting camera trick involves Lorre's dialogue with his own reflection, at a time when Lorre's character deteriorates from tormented genius into gleeful lunatic killer. Lorre's reflection, which represents his Mr. Hyde side, gives his Dr. Jekyll half some seriously bad advice.
Lorre's transition from miracle doctor into madman is the weakest aspect of the movie, even if it does cause Lorre to wear a wacky Brophy costume that gives him metal hands and re-attaches his head to his body. Although we all know that having the hands of a criminal will not make you perform criminal acts, this is a science fiction movie, which makes such nonsense acceptable.