THE INVISIBLE MENACE. Warner Brothers, 1938. Boris Karloff, Marie Wilson, Eddie Craven, Regis Toomey, Henry Kolker, Cy Kendall, Charles Trowbridge, Eddie Acuff, Frank Faylen. Director: John Farrow.

   I’ll admit it: I thought I knew who the murderer was, but I was wrong. Which just goes to show you that The Invisible Menace, although a somewhat clumsily filmed programmer, is worth watching until the very end. Combining humor with genuine pathos, this Warner Brothers murder mystery benefits from solid performances by star Boris Karloff and supporting actor Regis Toomey. Plus there are some occasional moments of levity and snappy dialogue to keep you engaged for the duration.

   When an ordinance expert on a military installation is found tortured and murdered, it’s up to an ornery colonel to figure out just what happened and why. Because the military base in question is set on an island, there’s a natural limitation as to whom the murderer might be. Is it one of the officers, the doctor, or perhaps Boris Karloff’s character, a man with a shady past and a secret from his time living and working for the U.S. Army in Haiti?

   At times extraordinarily stagy, The Invisible Menace has the feeling of a movie produced in 1931, rather than 1938. A lavish production this is not. But it’s a decent enough little crime film, one that doesn’t much linger in your thoughts afterward, but a clever enough adaptation of a play directed by an Australian living in the United States who would go on to much bigger and better things.