Actor, screenwriter, and novelist Arnold Yarrow, beloved for his guest appearance on Doctor Who, has died. Doctor Who News and Radio Times confirmed news of Yarrow’s passing in Dec. 10 reports, though details, including Yarrow’s cause of death, remain unclear. He was 104.

Born on April 17, 1920, Yarrow was considered to be the oldest surviving credited cast member of the long-running series, which got its start on the BBC in 1963. Yarrow joined the show in 1974, decades after first meeting future Doctor Who producer Barry Letts while acting in rep in the ‘40s, he told Toby Hadoke in 2020. He took on the role of Bellal, a member of the Exxilon species who assisted the Time Lord in battling the Daleks, in Death to the Daleks, appearing alongside Jon Pertwee’s Third Doctor and Elisabeth Sladen’s Sarah Jane Smith.

Stepping into the role of Bellal was no easy feat, though. Transforming into the character involved an elaborate costume, that had to be stitched and glued together.

“It was made of separate bits that were all glued together – I was stuck in there for three hours at a time,” Yarrow recalled. “They were very restricting. I was filled with horror the first time I put it on. There were two tiny pinholes for eyes to look out of and nostrils to breathe through. My vision was extremely limited.”

Dedicated to his work, the actor, who added that Pertwee had to guide him around set, said that before first stepping into the costume, he “visited a zoo and saw some marmosets and bush babies and this inspired me – looking at the way they conveyed their feelings. I thought the script echoed the underground Morlocks from The Time Machine.”

While memorable, Yarrow’s stint on Doctor Who was short-lived. The actor appeared in just three episodes in 1974. He told Hadoke that he wouldn’t have considered a longer stint. Reflecting on the role, he said, “It was a brief episode in a jobbing actor’s career.”

Outside of Doctor Who, Yarrow is also fondly remembered for his starring role on the British soap EastEnders. He starred as Dr. Bloom across 17 episodes from 1988 until 1989. His other acting credits include roles on Coronation Street, Dr Finlay’s Casebook, and Life with Cooper, per his IMDb profile. He also contributed as a script writer for shows including EastEnders and Softly, Softly.