"Mr. Keen, Tracer of Lost Persons" remained on the air for the next 18 years. Three different actors played the title role, Bennett Kilpack was Mr. Keen the longest, and Arthur Hughes saw the final show. Phil Clark also played the part. It was produced by Frank and Anne Hummert. The sponsors included Whitehall Pharmacal (as in Anacin, Kolynos Toothpaste, BiSoDol antacid mints, Hill's cold tablets and Heet liniment), Dentyne, Aerowax, RCA Victor and Chesterfield cigarettes. It aired on the NBC Blue network until 1947, when it switched to CBS.
Wikipedia | SHOP: Mr. Keen, Tracer of Lost Persons