The Blake's 7 star will join fun-loving Eddy Fox, an old friend of Alan Turner's, who turns up in style on a trike on July 13.
"I'm delighted to be appearing in Emmerdale," he told ITV.com.
He added: "My character Eddy's going to be great fun to play. I'll get to ride around the Dales on my trike in my leathers. I'll be like Marlon Brando."
"I'm also really looking forward to catching up with my old pal Richard Thorp (aka Alan Turner). We used to work together back on Emergency Ward 10."
By July 14, Eddy seems to have settled into the village, and while charming the ladies he makes Turner a tempting offer - to travel around the world with him.
Paul, 68, played loveable rebel Kerr Avon in Blake's 7. He has also popped up in Doctor Who, Law And Order UK, Little Britain and 007 epic Die Another Day.
Soap fans with long memories may also remember his brief appearance in Coronation Street in 1969, and in 2002 he popped up in Hollyoaks.