[2] He is remembered for his role as Chief Inspector Hubbard in Alfred Hitchcock's Dial M for Murder, as the chauffeur in Billy Wilder's Sabrina (both 1954), as Mr. Brogan-Moore in Witness for the Prosecution (1957) and as the second "Mr. French" on TV's Family Affair in its first season (1967).

He began his acting career on the English stage in 1916, appearing in J. M. Barrie's Peter Pan, Frances Nordstrom's The Ruined Lady, and Frederick Lonsdale's The Fake.

[2] In 1953, Williams won a Tony Award for Actor, Supporting or Featured (Dramatic) for his role as Chief Inspector Hubbard in Frederick Knott's Dial M for Murder on Broadway.

In the 1960 thriller Midnight Lace, starring Doris Day, Williams played a London police inspector much like his character in Dial M for Murder.

One of Williams' last performances was in 1979, playing alongside fellow actor Lorne Greene in a two-part episode of Battlestar Galactica titled "War of the Gods".

So many of the tunes of our well-known popular songs were actually written by the great masters—like these familiar themes...[5]In addition to his longstanding association with Hitchcock, Williams appeared in three Billy Wilder films over the course of his career: Sabrina (1954), Witness for the Prosecution (1957), and The Private Life of Sherlock Holmes (1970).