Laurie Johnson, who has died aged 96, was a prolific composer of classic television themes, including the punchy introduction to The Avengers, the expansive music for This is Your Life and the bouncy number for Animal Magic; he also wrote the catchy tunes for Lionel Bart’s 1959 stage version of Lock Up Your Daughters and the futuristic sounds that heralded the 1970s detective television series The Professionals.