Paul Rudd left speechless as Olivia Colman delivers prank call on ...

Paul Rudd was put on the spot after receiving a prank call from his long-time pal Olivia Colman.

The Ant-Man actor joined host Greg James on BBC Radio 1 this week when he received a surprise call.

He was helping callers with their personal problems when Olivia called in and pretended to be a Welsh woman.

It was Olivia's idea to prank call Paul when she heard he would be on the show.

She said she's a 'big fan' of the iconic actor and 'wanted to pick [his] brains' about a personal problem.

Olivia, posing as a random listener, asked: "What would you do if you had a really, like a really good mate, like for over 20 years like, and then this friend, yeah, he doesn’t live in England, but he’s come to England but he hasn’t told you about it?

"Then, not only has he not told you about it, he’s come on to a radio show. What would you do?"

Paul seemed uneasy as he answered: "Oh my god. Oh no," when Olivia asked if would be 'offended' if that happened to him.

"Personally, if it’s me? Absolutely not. I tend to give everybody the benefit of the doubt," he answered.

The actor continued laughing while repeating 'oh god'.

Thankfully, Greg put an end to Paul's suffering and told him that the mysterious is actually his pal Olivia.

After Olivia revealed who she is, Paul said: "By the way, I'm sweating. I'm actually sweating."

"You really can do every accent," he said before telling Greg that they 'go way back'.

On the other end of the call, Olivia explained: "Over 20 years! We were doing a play together and Paul used to come and stay on the floor of our rubbish flat in south London and come for Sunday lunch and things.

"Paul was properly in the play, and I had about two lines I think."

Olivia explained how she listens to the Breakfast Show and heard about Paul appearing on the show and decided to play a prank on him.

She emailed host Greg and asked if she could play a prank on him, to which Greg happily agreed.

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