Sam Neill, the versatile New Zealand screen actor who appeared in more than 150 productions over a five-decade career, and who was perhaps best known for his star turn as Dr. Alan Grant in the “Jurassic Park” series, died on Monday in Sydney, Australia. He was 78.

Mr. Neill’s family announced his death in a post on Instagram. “Sam was surrounded by family and passed with the dignity that has characterized his whole life,” it said.

Mr. Neill was diagnosed with angioimmunoblastic T-cell lymphoma in March 2022 and had been treated for it for years. His family said in the statement that he was “cancer free” when he died.

Born in Northern Ireland and raised in New Zealand, Mr. Neill, whose acting career began in the late 1960s, combined a credible Everyman quality with rugged good looks and a hard-to-place accent. He was cast in dozens of productions spanning genres, formats and continents.

Mr. Neill first came to international attention with the 1979 Australian period drama “My Brilliant Career.” Critics heralded him for nuanced portrayals, describing his “cryptic brusqueness” in one role and his “avuncular suavity tinged with a dignified sadness” in another.

His credits included the New Zealand films “The Piano” and “Hunt For the Wilderpeople,” the Hollywood blockbusters “Thor: Love and Thunder” and “Peter Rabbit,” and two seasons of the British television series “Peaky Blinders.”

“I’d like to think I’m able to suggest ambiguities and complexities in the people I play, because I think all of us have hidden aspects or contradictory qualities,” he told The Dominion Post, a New Zealand newspaper, in 2007. “I think that’s what makes us interesting as human beings, and that’s what makes human beings interesting to play.”

With few exemplars of international actors from a New Zealand background to follow, Mr. Neill said he had never set himself specific goals, allowing him to ricochet almost aimlessly from one project to the next.

“I never had a map, you know,” he told The Dominion Post in 2016. “There was no one else here that I knew of that had ever had a screen career.”

This is a developing story and will be updated.