Nicholas Benton "Ben" Alexander III (June 27, 1911 – July 5, 1969) was an American motion picture actor, who started out as a child actor in 1916. He is best remembered for his role as Officer Frank Smith in the Dragnet franchise. Nicholas Benton "Ben" Alexander III (June 27, 1911 – July 5, 1969) was an American motion picture actor, who started out as a child actor in 1916. He is best remembered for his role as Officer Frank Smith in the Dragnet franchise.