Van Dyke took a more dramatic turn in the 1990s. He starred in the popular crime drama Diagnosis Murder alongside his real-life son, Barry Van Dyke. Debuting in 1993, the series featured Van Dyke as Dr. Mark Sloan, a medical professional who helped the police solve crimes. The series ended in 2001, but Van Dyke didn't stay away from the small screen for long. He played another amateur detective in a series of TV movies, beginning with 2006's Murder 101. That same year, the actor appeared in the Ben Stiller comedy Night at the Museum.
His film work affected his TV career: the reviews he received for his role as D.A. Fletcher in Dick Tracy led him to star as the character Dr. Mark Sloan first in an episode of Jake and the Fatman, then in a series of TV movies on CBS that became the foundation for his popular television drama Diagnosis: Murder. The series ran from 1993 to 2001 with son Barry Van Dyke co-starring in the role of Dr. Sloan's son Lieutenant Detective Steve Sloan. Also starring on the same show was daytime soap actress Victoria Rowell as Dr. Sloan's pathologist/medical partner, Dr. Amanda Bentley, and Charlie Schlatter in the role of Dr. Sloan's student, Dr. Jesse Travis.[29] Van Dyke continued to find television work after the show ended, including a dramatically and critically successful performance of The Gin Game, produced for television in 2003 that reunited him with Mary Tyler Moore. In 2003, he portrayed a doctor on Scrubs. A 2004 special of The Dick Van Dyke Show titled The Dick Van Dyke Show Revisited was heavily promoted as the first new episode of the classic series to be shown in 38 years. Van Dyke and his surviving cast members recreated their roles; although nominated for a Primetime Emmy,[30][31][betterĀ sourceĀ needed] the program was roundly panned by critics. In 2006 he guest-starred as college professor Dr. Jonathan Maxwell for a series of Murder 101 mystery films on the Hallmark Channel.

In November 1959, Van Dyke made his Broadway debut in The Girls Against the Boys. He then played the lead role of Albert Peterson in Bye Bye Birdie, which ran from April 14, 1960, to October 7, 1961. In a May 2011 interview with Rachael Ray, Van Dyke said that when he auditioned for a smaller part in the show he had no experience as a dancer, and that after he sang his audition song he did an impromptu soft-shoe out of sheer nervousness. Gower Champion, the show's director and choreographer, was watching, and promptly went up on stage to inform Van Dyke he had the lead. An astonished Van Dyke protested that he could not dance, to which Champion replied: "We'll teach you". That musical won four Tony awards including Van Dyke's Best Featured Actor Tony, in 1961.[16] In 1980, Van Dyke appeared as the title role in the first Broadway revival of The Music Man.[17]
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