Donovan appeared in the Australian television soap-opera Neighbours, which, when shown on British television, commanded a considerable viewing audience of pre-pubescent/teenage girls who instantly took his character, Scott Robinson, to their hearts. His co-star Kylie Minogue had already begun to forge a career in pop music when he also signed to the Stock, Aitken And Waterman label, PWL.
In 1988 his first single, 'Nothing Can Divide Us Now', reached the UK Top 5. The follow-up was a collaboration with Kylie, 'Especially For You', which topped the UK charts in January the following year. Donovan consolidated his position as Britain's top teen pin-up by scoring four more Top 10 hits, including 'Too Many Broken Hearts' (a number 1 hit), 'Sealed With A Kiss', 'Every Day (I Love You More)' and 'When You Come Back To Me'. His album, Ten Good Reasons, reached number 1 and became one of 1989's bestsellers. His success the following year was endorsed by Top 10 hits in 'Hang On To Your Love' and a remake of the 1963 Cascades hit, 'Rhythm Of The Rain'. By this time Donovan had left the cast of Neighbours.
His performances in the stage show of the Andrew Lloyd Webber / Tim Rice musical, Joseph And The Amazing Technicolor Dreamcoat, at the London Palladium, drew sell-out crowds and mostly good reviews, taking many of his regular critics by surprise. A single from the show, 'Any Dream Will Do', reached number 1 in the UK chart, scotching any notion that Donovan was wavering as a hit-maker. He was perceived by many as simply being a teen-idol, yet his obvious talent in acting and singing, and the extent of his loyal following, echoed previous teen-idols made good as all-round entertainers ( Tommy Steele for example).
In the spring of 1992, Donovan won a libel action he brought against The Face magazine. Later in the same year, his high-profile concert tour was greeted with a good deal of apathy and critical derision ('Jason's big rock dream turns sour'), and it was considered by many to be a retrograde career move when he returned to Joseph And The Amazing Technicolor Dreamcoat the following year. For some time he alternated with other leading performers before taking over for the last few weeks before the show closed in February 1994.
After he had collapsed several times in public during 1995, there was inevitably speculation in the press regarding drugs and alcohol abuse. However, the following year he was in London playing Mordred in the Covent Garden Festival production of Camelot, and had his first non-singing role as a psychopath who keeps his first victim's head in a hat box, in Emlyn Williams's classic 1935 thriller, Night Must Fall, at the Theatre Royal Haymarket. Having also dressed in a black bin liner and Dr. Marten boots in order to host Mr. Gay UK, a beauty contest for men, he went one step further and donned the obligatory stockings and suspenders for the role of Frank 'N' Furter in an Australian production of The Rocky Horror Show. In 1998, he headed the 25th Anniversary tour of that cult show in Britain.