In 1967 Holm won a Tony Award for Best Featured Actor in a Play as Lenny in "The Homecoming" by Harold Pinter. In 1977, Holm appeared in the television mini-series "Jesus of Nazareth" as the Sadducee Zerah, and a villainous Moroccan in "March or Die". The following year he played J. M. Barrie in the award-winning BBC mini-series "The Lost Boys", In 1981, he played Frodo Baggins in the BBC radio adaptation of J. R. R. Tolkien's "The Lord of the Rings".