Actor Nicky Katt was found dead at his apartment in Burbank, California, on Tuesday. He was 54.

Katt’s attorney, John Sloss, first confirmed his client’s death to the press on Sunday, but offered no further details.

On Monday, Katt’s family told the public he had died by suicide after long “battling with depression” he fought “bravely but quietly.”

“This is a pain no family should endure, yet far too many do,” his sister Elise Ravenscroft told Deadline. “Mental illness is real, it is powerful, and it is often invisible. We hope that by sharing this, we can help break the silence and stigma that so often surrounds mental health struggles.”

A native of South Dakota, Katt began his career as a child actor, making his screen debut in a 1980 episode of “Fantasy Island.”

He went on to land recurring roles on TV’s “Herbie, the Love Bug” and voiced Leland Lizard in the children’s cartoon “The Get Along Gang.”

As an adult, Katt carved out a niche playing menacing, morally murky characters, from high school bully Clint Bruno in Richard Linklater’s ’70s-set coming-of-age classic “Dazed and Confused” to a white supremacist child rapist in the 1996 legal drama “A Time to Kill.”

On the small screen, Katt spent three seasons on David E. Kelley’s drama “Boston Public,” where he brought unexpected depth and empathy to the rebellious geology teacher Harry Senate.

He also had credits in “Love & War,” “Friends,” “Batman & Robin,” “Rules of Engagement,” “School of Rock,” “King of the Hill,” “Monk,” “Law & Order” and “Death Proof.”

His final screen appearance was a 2018 guest role on the Hulu comedy “Casual.”

Though Katt once hinted at leading man aspirations in a 2002 interview with the Los Angeles Times, he admitted he was drawn to darker, more complex roles.

“Sometimes I think if I did more sit-ups and went to the tanning salon, I could have a lot more power than I do now,” he said. “At the end of the day, you do what your gut tells you to do.”