With his soft, hurt eyes, rugged features and broken nose, Roy Scheider had the look of a trammelled hero. A star of some of the most admired thrillers of the 1970s, he usually played heroic characters beset by obstacles — their partners, their commanders or their vices. He will be most remembered for Jaws — one of the few films in which his character is still alive when the end credits roll. His greatest regret, however, was that he never returned to the stage to play the classical hero roles that were his calling for 15 years.

Roy Richard Scheider was born in Orange, New Jersey, in 1932. He developed rheumatic fever at 6 and spent much of the next decade in bed. Once recovered, he embraced sport, especially boxing, and had his nose broken while participating in the preliminary round of a Golden Gloves youth competition. He attended Rutgers University in New Jersey, where he joined the theatre group. He went to Franklin & Marshall, a liberal arts college in Lancaster, Pennsylvania, and appeared in a student production of Billy Budd. Encouraged by the response, he took a role in Coriolanus.

After four years with the US Air Force in Korea, Scheider won a leading stage role in 1961, playing Mercutio in the New York Shakespeare Festival production of Romeo and Juliet. He spent the next few years in repertory theatre, while flirting with television roles. He was 32 before he appeared in a film, the ponderous Gothic horror The Curse of the Living Corpse. After that he scraped by in uncredited roles and television bit-parts before playing a gangster in the movie of the unlikely Harold Robbins story, Stiletto, in 1969.

Fortunately better things awaited in 1971, when he helped a clutch of other people to win awards. He played Jane Fonda’s pimp in Klute, a film which rode on the notoriety of Fonda’s antiVietnam war stance and won her an Oscar for Best Actress. His real break came later in the year with The French Connection, in which he played Buddy “Cloudy” Russo, sidekick to Gene Hackman’s swearing, bullying racist, Jimmy “Popeye” Doyle. The film took three Academy Awards and set new — slightly contradictory — benchmarks for cinematic realism, car chases and a narrative which eschewed almost every sentimentalist Hollywood tradition.

His turn for top billing came with Jaws in 1975, when he played the Amity sheriff Martin Brody. This was Steven Spielberg’s first big budget production, and his technical brilliance, plus the deathless score by John Williams, made the film the first to take more then $100 million. Scheider’s laconic line, “You’re gonna need a bigger boat”, was voted 35th best movie quote by the American Film Institute in 2005.

The script directed that when Brody discovers the shark’s first victim, “whatever he sees has a marked effect on his entire physique”. This moment captured Scheider’s face, halfway between horror and disbelief, in a pioneering “forward tracking zoom out” shot which became a signature moment — known to film students thereafter as “the Jaws shot”. With this the filmgoer enters what Scheider termed “the human moment”, which “opens the door to humanity, to wholeness”. Here the conscience of Brody, probably one of the most fully realised heroes of any Hollywood thriller, is laid open. After Jaws, Scheider was a true Hollywood contender.

Scheider appeared in John Schlesinger’s Marathon Man (1976), where he was stabbed in the stomach by Laurence Olivier after meeting his brother, Babe Levy, played by Dustin Hoffman. He was rostered to play the part of Michael Vronsky in The Deer Hunter, but the part went to Robert De Niro when Scheider questioned the film’s ending. To fulfil his Universal contract he agreed, somewhat reluctantly, to take part in Jaws 2. Sequels were a very new and controversial idea, and The French Connection II had recently been shot down by critics. Jaws 2, cursed by production gremlins, snubbed by Spielberg and finally finished off by the television director Jeannot Szwarc, pushes Brody to new levels of endurance when he is fired and his own sons are attacked. Featuring another fine score by John Williams, it was not a bad film, praised more in retrospect than upon its release. Scheider had no part in the follow-ups which starred Dennis Quaid and Michael Caine.

Although his abilities gave saving grace to even the most pointlessly gung-ho scripts — such as Blue Thunder in 1983 — Scheider inexplicably fell from favour with casting directors. His later work was in hit-and-miss productions and involved a great deal of dying: he shot himself in Cohen and Tate (1989), was buried alive by Gary Oldman in Romeo is Bleeding (1993), shot in the neck in The Rage (1997), blown up in Time Lapse (2001) and was gunned down by John Travolta’s killers in The Punisher (2004). He turned the tables last year, appearing as a serial killer in an episode of Law & Order.

His favourite role remained that of the pill-popping anti-hero Joseph “Joe” Gideon in All That Jazz (1979), who slips away during heart surgery in a moving musical sequence. This part got him his second Oscar nomination. Scheider never won a major award.

Scheider lived in the Hamptons, New York State, but spent much of his time in Florence with his family. There he developed Renaissance Park, a 212-acre project in an old munitions factory, equipping it with a sound stage and hoping to draw international filmmakers, directors, artists and choreographers.

A campaigning environmentalist, Scheider was part of Group for South Fork Environment and the Three Mile Island group, and was one of a group of people who lay across US Highway 27 to protest against the US invasion of Iraq.

In 2005, suffering from cancer, he chose not to take part in the 30th anniversary of Jaws, stating: “I’ve had enough Jaws to last four lifetimes. I’m very happy the movie is as successful as it is, but I don’t need to celebrate it any more.”

He is survived by his second wife, Brenda, and their two children, and by a daughter from his first marriage.

Roy Scheider, actor, was born on November 10, 1932. He died on February 10, 2008, aged 75