Yes, THARK is an exclamation by a person who sees a ghost in this delightfully dippy haunted house comedy...and so you can easily see the risqué joke in the title. Today of course they just bellow F**CK. There were many haunted house comedies of this period generally between versions of the Cat And The Canary and right up to Abbott and Costello Meet Frankenstein or even Francis in a Haunted House. One of my favorite British scare comedies is The Haunted Lighthouse from about 1934. THARK (say it out loud) borrows also from The Cat Creeps, The Bat Whispers and any other films post 1927 lifted from plays about specters and weird butlers and stormy nights in a mansion, a burglary and perhaps a murder. See also THE PHANTOM OF CRESTWOOD. As far as rude movie titles go, it is a beauty and not bettered until THE AMAZING DR CLITTERHOUSE (clitoris) of the 40s. Hilarious!