He became an icon of Swinging London for his portrayal of a trendy fashion photographer in the critically acclaimed film Blowup (1966), directed by Michelangelo Antonioni.

[1][2][3] During the 1960s and 70s, Hemmings played both leading roles and major supporting parts in films like Camelot (1967), The Charge of the Light Brigade (1968), Barbarella (also 1968), Alfred the Great (1969), The Walking Stick (1970), Juggernaut (1974), Deep Red (1975), Islands in the Stream (1977), and The Prince and the Pauper (also 1977).

Britten's interest in Hemmings ceased abruptly from the moment his voice broke, which occurred unexpectedly while he was singing the aria 'Malo' during a performance of The Turn of the Screw in 1956 in Paris.

[10] The resulting film was a critical and commercial sensation for MGM, which financed it, and helped turn Hemmings and Vanessa Redgrave into stars.

"[11] After Blowup Hemmings accepted an offer from Warner Bros to play Mordred in the big-budget film of the Broadway musical Camelot (1967).

Hemmings was then cast as Louis Nolan in the big-budget epic The Charge of the Light Brigade (1968),[6] which, like Camelot, was widely seen but failed to recoup its cost.

Around 1967 Hemmings was briefly considered for the role of Alex in a film version of Anthony Burgess's novel A Clockwork Orange (1962), which was to be based on a screen treatment by satirist Terry Southern and British photographer Michael Cooper.

[12] Hemmings costarred with Richard Attenborough in the crime comedy, Only When I Larf (1968), then was the sole star of an anti-war film, The Long Day's Dying (1968).

More financially successful was the science fiction sex comedy Barbarella (1968), starring Jane Fonda in which Hemmings had a key supporting role.

He played the lead in two period films for MGM: a comedy, The Best House in London (1969), and the historical epic Alfred the Great (1969), in which Hemmings had the title role.

Hemmings was cast in further lead roles at the start of the 1970s : The Walking Stick (1970) with Samantha Eggar for MGM; Fragment of Fear (1970), a thriller; and Unman, Wittering and Zigo (1971).

Hemmings appeared in the Italian giallo film Profondo Rosso (also known as Deep Red or The Hatchet Murders) (1975) directed by Dario Argento.

He also had support roles in The Squeeze (1977), The Prince and the Pauper (1977), The Heroin Busters (1977), The Disappearance (1977), Squadra antitruffa (1977), Blood Relatives (1978), Power Play (1978) and Murder by Decree (1979).

Hemmings then received an offer from Antony I. Ginnane to direct the Australian horror film The Survivor (1981), based on James Herbert's 1976 novel of the same name, starring Robert Powell and Jenny Agutter.

He directed the drama film Dark Horse (1992) and as an actor returned to the voyeuristic preoccupations of his Blowup character with a plum part as the Big Brother-esque villain in the series-three opener for the television horror anthology series Tales From the Crypt.

[citation needed] He also appeared in the horror film Blessed (2004) with Heather Graham, which was dedicated to his memory after a fatal heart attack while on set.

Hemmings was married four times: to Genista Ouvry (1960–1967), actress Gayle Hunnicutt (1968–1975), Prudence de Casembroot (1976–1997), and Lucy Williams (2002 to his death).

At their outdoor wedding, Henry Mancini conducted an orchestra and the Mamas and the Papas performed next to a swimming pool filled with doves dyed puce.

Their marriage ended when Hunnicutt discovered Hemmings's affairs with actress Samantha Eggar (his co-star in The Walking Stick (1970)), and his secretary Prudence de Casembroot.

[citation needed] Hemmings suddenly died in 2003 at age 62 of a heart attack, in Bucharest, Romania, on the film set of Blessed (working title: Samantha's Child) after he had performed his scenes for the day.