Bob was born Robert Digby Bosher on the 9th October 1932 in Wembley Middlesex, to Iris Rousham (aka Barbara or Peggy) and John Bosher, a newspaper editor. His mother’s second husband, William McBain (aka Mac), adopted Bob at the age of 11 and after attending prep school in Golden Manor, Bob studied at Ardingly College, Sussex. He spent his National Service as a lieutenant in the Intelligence Corps, studying Russian at London University.

After training at the Central School of Speech and Drama, and several years in Rep at Glasgow, Cheltenham and Salisbury, Bob made his West End debut in Julian Slade's Follow That Girl in 1960. He also appeared in Julius Caesar at the Royal Court; Jingo with the RSC ; St Joan at the Old Vic and Tom Stoppard's Dirty Linen at the Arts Theatre. In 2000, he played Gonzalo in The Tempest at Shakespeare's Globe, and in 2002, Chebutykin in The Three Sisters at the Orange Tree, Richmond (one of 25 appearances there over the years).

Bob also made over a hundred and fifty television appearances: From Z Cars and Upstairs Downstairs to Fawlty Towers and The Professionals; his most recent being Casualty, late in 2003. His films include Breakout, Bullseye and A Fish Called Wanda.