The 78-year-old actor, best known for his role as the sixth incarnation of the Doctor, will arrive in the village later this month playing mystery man Michael.
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When Diane (Elizabeth Estensen) arranges a date at The Woolpack, she's looking forward to meeting someone new.
But she is entirely unprepared for her date's unusual passion - what is it, and will she be impressed or disappointed by Michael?
Baker said of his new Emmerdale role: "I am so old that I remember watching Emmerdale Farm long before it became just Emmerdale when my friend (and colleague from Doctor Who days) Frazer Hines was a youthful Joe Sugden and the wonderful Arthur Pentelow was in the cast.
"So to get a call to join the cast, albeit briefly, as a possible love interest for Elizabeth Estenson, an actress I had long admired, certainly appealed to me.
"A bonus was the fact that also in my scenes was Rodney Blackstock, played by my old friend Patrick Mower."
Baker, who didn't say how many episodes he would be in the village for, teased: "I enjoyed my COVID-compliant time with both of them in Leeds inordinately. As to what happened, well you'll just have to watch and find out. It's a bit of a puzzle actually!"
This might be the first time Baker has appeared in Emmerdale, but he isn't a complete stranger to soap land.
Back in 2000 he played a judge for one episode in Hollyoaks, and over the years he has popped up in Doctors a few times as a range of different characters.
Hollyoaks is set to welcome Jamelia as a guest star this month as part of their Black to Front episode, where she will play a friend of Martine Devereux (Kelle Bryan).
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