Dame Diana Rigg and her daughter Rachel Stirling have been cast in the next series of Doctor Who.
The pair will appear in a 2013 episode written by Mark Gatiss, specific plot details have been kept under wraps, however it is believed that they will replicate their real-life relationship as a mother and daughter on screen.
In a statement, Stirling described her role on the BBC sci-fi as a "joy", adding: "I am looking forward to the madness of Doctor Who enormously.
"Mark Gatiss has written a gift of a script and an on-screen relationship between Ma and I that is truly delicious.
"We have never before worked together because the offers have not been tempting, but when such a funny and original script comes through you know the time has come."
David Warner (Titanic), Liam Cunningham (Game of Thrones), Jessica Raine (Call the Midwife) and Dougray Scott have also landed guest roles in Doctor Who's seventh series, which sees Jenna-Louise Coleman replace Karen Gillan as the assistant to Matt Smith's Time Lord.
Fans will see six episodes of the long-running sci-fi show this year with eight more in 2013. The premiere episode Asylum of the Daleks will be screened for the time at BFI Southbank in London on August 14.
Filming of the episode begins this week at Roath Lock Studios in Cardiff.