William Bennett Kilpack (February 6, 1883 – August 17, 1962)

Mr. Keen, Tracer of Lost Persons was one of radio’s longest running shows,
airing October 12, 1937 to April 19, 1955, continuing well into the television
era. It was produced by Frank and Anne Hummert, who based it upon Robert
W. Chambers‘ 1906 novel The Tracer of Lost Persons. The sponsors included
Whitehall Pharmacal, makers of Anacin,Kolynos Toothpaste, BiSoDol antacid
mints, Hill’s cold tablets and Heet liniment), Dentyne, Aerowax, RCA Victor and Chesterfield cigarettes. The 15-minute serial initially aired on the NBC Blue
network until 1947, when it switched to CBS and became a weekly half-hour
show. Bennett Kilpack (above) was the longest-running Mr. Keen.