Following military service and a brief boxing career, Mullard found work as a cockney character actor in film and TV comedy, notably in the series Romany Jones.
It was on television that Mullard made a name for himself, first as a straight man for Tony Hancock, Frankie Howerd and Benny Hill, then in The Arthur Askey Show.
It was the London Weekend Television series Romany Jones, first aired in 1973, which gave Mullard his highest profile, playing Wally Briggs, a crafty caravan-dweller.
[7] So popular was Mullard's character that a sequel, Yus, My Dear, was broadcast in 1976, in which Wally and his wife Lily (Queenie Watts) had moved out of their caravan into a council house.
He entered the UK Singles Chart in 1978 with his cover of "You're the One That I Want" (Pye 7N 46121) (from the film Grease), a duet with fellow comedy actor Hylda Baker, who was in her seventies.
The single was his last professional success during Mullard's life; there followed an uncredited narration on the Glenn Close-led live-action 101 Dalmatians, released in 1996, after his death.
Mullard continued to live in a council house in Islington after his success and spent much of his free time socialising in local pubs.
[11][12][13] In May 1996, five months after his death, the Sunday Mirror reported that a This Is Your Life episode about Mullard had been planned, but it was cancelled by host Eamonn Andrews.
[14] Mullard's wife Florence had committed suicide in 1961 by taking an overdose of sleeping tablets, after suffering from poor physical and mental health for several years.