"Doctor Who" is getting a dose of "The Avengers" ... no, not the box office smash hit, but the fan-favorite 1960s series. Dame Diana Rigg has signed on for a "Doctor Who" guest spot.

According to BBC, Rigg, known as Emma Peel to "Avengers" fans, and her daughter Rachael Stirling will star side-by-side in an episode of "Doctor Who" set to air in 2013. This will be the first time the two have worked together on screen.

BBC is keeping the character details under wraps, but Rigg and Stirling will appear as a mother and daughter with a dark secret opposite Matt Smith and new cast member Jenna-Louise Coleman.

“The first time Rachie and I will be working together is on an episode of 'Doctor Who' specially written for us by Mark Gatiss," Rigg said in a statement. "How lucky is that?”

"Doctor Who" returns to BBC One in the fall, with five episodes and a Christmas special. An additional eight episodes are set to air in 2013.

“Dame Diana Rigg, Rachael Stirling and a Mark Gatiss script -- a combination of talents you could only get in 'Doctor Who,'" Steven Moffat, executive producer and head writer, said in a statement. "Frankly, I'm terrified already!"

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