French and Saunders share photo with Judi Dench from their Comic Relief 'Repair Shop' sketch

Screen superstar Dame Judi Dench is set to join Dawn French and Jennifer Saunders in a Repair Shop sketch for Comic Relief and the comedians have released a sneak preview of their day on set together.

French and Saunders had already been announced to be reprising their characters The Extras in a special episode of The Repair Shop, but they'll also be joined by a very well known guest.

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Sharing a photo from filming of James Bond star Dench, 87, sitting between the duo who are in costume as elderly women, French wrote on Thursday: "Dench lookin mighty delighted to finally be in a French & Saunders sandwich. Watch tmw night ⁦@comicrelief. Who can see a sexy pop sock…?"

Although Dench's exact part in the sketch isn't known, BBC One has also released a clip of French and Saunders meeting Repair Shop host and expert Jay Blades in the episode.

The show is known for guests asking Blades and co to mend items with sentimental value that often come with an interesting history and emotional story attached.

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But the two women open a bag to reveal that they have brought along a broken toaster and start to explain to an incredulous Blades how it works.

French then attempts to pull at the heartstrings as she tearfully says: "I'm going now, because I used to really enjoy making toast with my son, but he's gone now."

Blades asks: "He's not with us any more?"

Saunders replies: "He's in Dubai. They don't make toast in Dubai," as French adds: "It's against their culture, I believe, Jay Blades."

But Blades tells them: "We don't do toasters. We've never done toasters."

French and Saunders aren't the only comedy duo to look out for in tomorrow night's charity broadcast - David Walliams and Matt Lucas will be back together for a rare sketch as they offer a new Rock Profile.

The Little Britain stars have hardly worked together over the last decade, but a promotional photo shows them in costume as father and daughter musicians Billy-Ray and Miley Cyrus.

Comic Relief airs tomorrow from 7pm on BBC One.

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