Actor Stan Kirsch, best known for roles in the Highlander TV series and sitcom Friends, has died at the age of 51.
The star played Richie Ryan in the fantasy sci-fi adventure show, a spin-off from the 1986 film.
In 1995, Kirsch made a memorable cameo in Friends in an episode titled The One with the Ick Factor.
He played Ethan, a young man dating Courteney Cox's character Monica, who lied about his age because he was a senior high school student.
A message on the Stan Kirsch Studios Facebook page read: "We tragically lost our beloved Stan Kirsch on January 11th."
His widow Kristyn Green added: "I want to thank everyone for the outpouring of love and support."
After appearing as a child actor, Kirsch took up what would become his signature role on the Highlander TV spin-off in 1992, portraying the teenage Ryan - a streetwise and quick-witted petty thief.
The show's official Facebook page also paid tribute, noting his importance to the series and how he "even changed himself physically" to reflect how the character would have had to have survived in the world of "the immortals".
"Without Stan Kirsch, Highlander: The Series would have been far less," they said. "He brought a sense of humour, kindness and youthful enthusiasm to the character of Richie Ryan for six seasons."
Kirsch's final acting role, voicing several characters in the animated series Invincible, came in 2009.
He made his debut as director and producer in 2004 with the film Straight Eye: The Movie. He went on to found his Los Angeles-based studio and acting school with Green in 2008, helping other actors into screen and stage roles.