Having been told he resembled Doyle's creation for years,[2] Wontner was finally cast in the role for The Sleeping Cardinal in 1931. Wontner was noticed after portraying Sexton Blake at the Prince Edward Theater in 1930.[2]
Wonter was fifty-six when he began portraying Holmes[3] and was forced to wear a toupée in the first three films to hide his bald spot.[3] Holmes in the novels had retired at age fifty[4] and as such, Wontner was technically too old for the part.[4]
In 1935, Wontner returned to the role for The Triumph of Sherlock Holmes. For this film, Wontner jettisoned the toupée[6] and Ian Fleming returned to the role of Dr. Watson.[7]Lyn Harding took over the role of Professor Moriarty from Norman McKinnel, and Charles Mortimer took over the role of Inspector Lestrade from Philip Hewland. Wonter's age, fifty-nine by this time, was too difficult to hide so Holmes is on the verge of retiring.[6][7] The film is a very accurate[6] adaptation of The Valley of Fear.[7] The film received rave reviews[7] which would lead to one final film.
In 1937, Wontner's final Holmes film, Silver Blaze, was released in Britain. Ian Fleming returned for a final turn at Dr. Watson, as did Lyn Harding as Moriarty while John Turnbull became the third actor to play Inspector Lestrade.[6] The production was far less faithful than previous films, injecting Sir Henry Baskerville from The Hound of the Baskervilles into this adaptation of "The Adventure of Silver Blaze".[6] The film wasn't released in the U.S. until 1941 by which time it had undergone a retitle to Murder at the Baskervilles.[8]
Wonter's performances as Holmes were highly praised.[11] Lionel Collier wrote in Picturegoer, "Arthur Wontner is a perfect Sherlock Holmes."[7]Vincent Starrett, one of the founders of the Chicago chapter of the Baker Street Irregulars, said of Wontner's performance as Holmes, "Surely no better Sherlock Holmes than Arthur Wontner is likely to be seen and heard in pictures, in our time."[12]