The Invisible Ray

Dr. Janos Rukh discovers a certain type of radium that has almost magical healing properties. But the element has a dangerous side, too, and it has already started affecting Rukh. Consumed by paranoia, he begins to suspect that his wife is having an affair. Wild for revenge, Rukh hatches a deadly plot...using his own poisoned body as a weapon to kill.

• John ColtonScreenplay
• Lambert HillyerDirector
• Franz WaxmanOriginal Music Composer

• Boris KarloffDr. Janos Rukh
• Bela LugosiDr. Felix Benet
• Frank LawtonRonald Drake
• Frances DrakeDiana Rukh
• Violet Kemble CooperMother Rukh
• Beulah BondiLady Arabella Stevens
• Walter KingsfordSir Francis Stevens
• Paul WeigelMonsieur Noyer
• Frank ReicherProfessor Meiklejohn
• Georges RenaventChief of the Surete
• May BeattyMme. LeGrand (uncredited)
• Paul McAllisterPapa LaCosta (uncredited)