He also had memorable roles as Captain Edward Smith of the RMS Titanic in A Night to Remember (1958), the First Sea Lord in Sink the Bismarck!

He attended All Saints Choir School, Margaret Street, London, and was a chorus member for a 1927 production of the George Gershwin musical Oh, Kay!.

In 1965, Naismith played the title role of the Virginia statesman George Mason in the NBC documentary series, Profiles in Courage.

William Bakewell played George Wythe in the episode, and Arthur Franz was cast as James Madison.

Naismith played the Prince of Verona in the BBC Television Shakespeare version of Romeo and Juliet.