Bitter and crazed ex-military officer Paul Krenner (an excellent performance by James Griffith) forces kindly scientist Peter Ulof (a sturdy turn by Ivan Triesault) to create an invisibility process using radiation. They proceed to break volatile safe cracker Joey Faust (robustly played with venomous aplomb by Douglas Kennedy) out of jail so he can steal more radium, but things don't go according to plan. Director Edgar G. Ulmer, working from an engrossing script by Jack Lewis, relates the compelling story at a steady pace and maintains an appropriately serious tone throughout. Margueritte Chapman does well as greedy and treacherous moll Laura Matson. The bank robbery set piece is a lot of fun (Faust turns visible again in the middle of the gig!) and the thrilling conclusion ends with a literal explosive bang. Both Meredith M. Nicholson's sharp black and white cinematography and Darrell Calker's moody score give this picture a cool film noir-style atmosphere. The special effects are admittedly rough, but overall decent and acceptable. The tight 57 minute running time ensures that the movie never becomes dull or overstays its welcome. A neat little flick.