The actor, 66, said it happened when they co-starred in a production of Chekhov’s The Cherry Orchard in the West End in the 80s and that it was so funny she wet herself.
Reminiscing on Graham Norton’s talk show, Manville said Dame Judi could be 'so naughty'.
She said: “We were in The Cherry Orchard and I was on stage on my own and she was in the wings trying to make me laugh. She was pretending she was being pleasured from behind!
“I laughed so much I wet myself.”
Manville went on: “Luckily I had a long dress on but the stage was raked and I could see my pee trickling down and over the edge into the stalls.
“She is so naughty!”
Dame Judi, 87, is known to have a cheeky sense of humour.
It was once reported that she sometimes had a bit of fun with co-stars by embroidering rude sayings onto things for them.
Her Pride And Prejudice co-star Matthew MacFadyen was quoted as saying in a 2005 interview with Premier magazine: "She makes these like needlework embroideries on set in the tedium of filming but they are all, 'You are a ****'."
Co-star Keira Knightley chimed in: “She just sits there and she embroiders and you think, 'Oh, that's so nice! It's Judi Dench. It's so quaint; she's embroidering a cushion', and you go, 'What are you embroidering?'
"And (it says), 'F***!'”
The Graham Norton Show is on BBC One on 7 October at 10.40pm and is also available on BBC iPlayer.
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