Webb was initially cast as Emperor Palpatine in Richard Marquand's Return of the Jedi, but fell ill before he could fulfil the role and passed months after.

[1][2] He was educated at Bramcote School, Scarborough, North Riding of Yorkshire and Royal Naval Colleges Osborne and Dartmouth.

[3] Webb made his first professional appearance on the stage at the Century Theatre, Bayswater in April 1924, as Lawyer Hawkins in The Devil's Disciple with the Lena Ashwell Players, with whom he remained until 1926.

[2] After shorter spells with J.B. Fagan's Oxford Players (1926–28) and the Masque Theatre Company in Edinburgh and Glasgow (1928) he had small roles in three West End productions.

[11] Long after their affair had finished, Coward cast him in the important role of Punalo Alani in South Sea Bubble in 1956.

[12] Webb made his Broadway début in Tonight at 8.30 in 1936,[2] and appeared again there the following year as Roger in Coward's production of Gerald Savory's comedy George and Margaret.

In the late 1940s, resuming his stage career, he acted and in the West End, on Broadway, and on tour in the US, the latter in Terence Rattigan's The Winslow Boy.

[2] Webb's other stage roles during the 1950s included Sir Timothy Bellboys in John Whiting's A Penny for a Song (London, 1951), William Collyer in Rattigan's The Deep Blue Sea (New York, 1952), Eggerson in T. S. Eliot's The Confidential Clerk (Edinburgh and London, 1952), Sir Toby Belch in Twelfth Night, the King of France in All's Well That Ends Well and Marcus Andronicus in Titus Andronicus (Shakespeare Memorial Theatre Company, Stratford-on-Avon, 1955), and three Shaw roles, Lord Summerhayes in Misalliance (Lyric, Hammersmith, 1956), Andrew Undershaft in Major Barbara (Royal Court, London, 1958) and Mazzini Dunn in Heartbreak House (1959, New York).