《煤气灯下》是一部由英国地区于1940年出品的悬疑类电影。该片由帕特里克·汉密尔顿、阿瑟·理查德·罗林森、布里奇特·博兰担任编剧，Thorold Dickinson亲自指导拍摄。主要演员包括Anton Walbrook、Diana Wynyard、Frank Pettingell等英国著名影星。
Twenty years ago, old Mrs. Barlow was killed in her home at 12, Pimlico Square for her priceless rubies. The murderer searched the whole house without finding them, then disappeared. The house has been empty since then, but now Paul and Bella Mallen move into the apartment. Bella Mallen suffers from forgetfulness and nervousness - at least that is what her hu*and tells her. An elderly horse wrangler, B.G. Rough worked as a policeman twenty years ago and still remembers the unsolved case. He notices that Mr. Mallen looks just like Louis Barre, Mrs. Barlow's nephew. And why does Mr. Mallen so mysteriously le*e every night just to go into the apartment next door, nr. 14?