Walter Koenig, the actor known for playing Pavel Chekov throughout the Star Trek franchise, has died, his representative confirmed to the Hollywood Reporter. He was 90.

Koenig died at his home in North Hollywood surrounded by his daughter and niece, according to a Facebook post by Zachery McGinnis, the founder of Galactic Productions, an appearance agency that counted the actor as one of its clients. His death was attributed to “old age”, with no other details provided.

“Today we mourn the passing of Walter Koenig, whose talent, warmth, and unforgettable performances left a lasting mark on generations of fans around the world,” McGinnis wrote. “Walter’s legacy extends far beyond the screen. Through countless convention appearances and interactions with fans, he shared his kindness, wit, and appreciation with everyone fortunate enough to meet him. He understood what Star Trek meant to people and embraced the community that grew around it.”

The post concluded: “Thank you, Walter, for the memories, the inspiration, and for boldly going where few have gone before.”

“My heart is heavy,” wrote Koenig’s Star Trek co-star George Takei on Facebook on Monday. Takei first met Koenig in the 1960s, “on the bridge of the Enterprise” and remained friends for six decades; Koenig served as Takei’s best man at his wedding in 2008.

“Walter was more than Chekov. He was a writer, a teacher, a thoughtful man, and a loyal friend,” Takei wrote. “To the fans who loved him for so many years, thank you. He loved you too. Rest well, my dear friend. Keep navigating a steady course.”

Jesse Thorn, the host of the NPR show Bullseye, also confirmed the news on Bluesky, citing his friend Danielle Koenig, the late actor’s daughter. “Something I was struck by knowing Danielle, her husband and her late brother Andrew (and talking with George Takei) was the very sincere love those Star Trek cast members had for each other,” he wrote. “That whole thing was thrust upon them and their obvious deep friendship was so clear. What a gift.”

Born in Chicago but raised in Manhattan as the child of Lithuanian immigrants, Koenig began his acting career in 1962, with an uncredited role as a sentry in Combat!. He joined Star Trek for the start of the second season and appeared in 36 of the 50 episodes that aired between 1967 and 1969.

He continued his role as the Russian Chekov in the first seven Paramount movies derived from the show, released between 1979 and 1991, as well as in a two-part crowdsourced Renegades series that debuted online in 2017. He most recently appeared in a cameo for a 2023 episode of Star Trek: Picard, voicing Anton Chekov, the son of his original character.

Koenig also worked as a writer, penning episodes for such series as The Powers of Matthew Star, Family, Land of the Lost and The Incredible Hulk. He wrote, produced and starred in the 2010 sci-film InAlienable, starring Richard Hatch.

Koenig was married to the actor Judy Levitt, with whom he appeared in three Star Trek movies as well as another acclaimed sci-fi series, Babylon 5, which ran from 1994 until 1998. The couple were together from 1965 until her death in December 2022 at the age of 83. Their son Andrew, who played Richard “Boner” Stabone in the ABC sitcom Growing Pains, died in 2010 at age 41.

Koenig is survived by his daughter, the actor and screenwriter Danielle Koenig.