His career took off in the 1950s, when he became a supporting star of the British film industry in such films as The Colditz Story, opposite Eric Porter and John Mills, and Two-Way Stretch opposite Peter Sellers. He offered a brute performance as the loutish Marquis of Queensbury in The Trials of Oscar Wilde, starring Peter Finch.
By age 19 he had lost his hair, and an ill-advised experiment with a toupee did not end well (he claimed it looked like a dead moth on a boiled egg). He attended RADA, as the only bald student, and was soon making stage appearances in Lorca and Giraudoux. In addition to a booming film career, he often returned to the stage, and appeared on Broadway in 1987, playing Pickering opposite Peter O'Toole's Henry Higgins and Amanda Plummer's Pygmalion.
In the 70s, he became a film writer and director of some note with his production of The Railway Children, considered by some to be a classic of the family film genre. (He bought the film rights at the insistence of his young daughter for 600 pounds.)
Jeffries is well-remembered for his appearances in two film musicals of the late 60s. He played King Pellinore in the all-star Camelot, opposite Richard Harris and Vanessa Redgrave, and in 1968, contributed a charming performance opposite Dick Van Dyke in Chitty Chitty Bang Bang. It is from this classic children's musical that the following clip is plucked. You don't really need to know the details, do you? Surely everybody knows the story of the flying, floating, magic car, and the attempts by the evil Baron Bomburst of Vulgaria to steal the invention. Jeffries's performance as Grandpa Potts is a scene stealer, spending much of the film in an outhouse, which, as you can see, is being abducted by the villains in this clip.
Chitty Chitty Bang Bang had a score by the Sherman Brothers, working off the Disney lot this time, and was based on a fantasy novel by Ian Fleming, of James Bond fame. Jeffries plays Dick Van Dyke's father in the film, though was himself six months younger than the star. It's a marvel what a bald head and a grey beard can do. Enjoy: