Melissa McCarthy finds it "crazy" Susan Sarandon agreed to star in 'Tammy'

She said: "Oh, my God! How crazy is that?

"I couldn't believe it when we... She was our dream person to go out to. And we hemmed and hawed. Like, 'Do we even have a chance of it?

Will she ever read it?'

" And then we thought, 'We have to start with our absolute dream wish.

We have to. And then if we get rejected, we continue on.' And next thing you knew, we were going to have a phone call with her, and Ben and I couldn't believe that.

"And the next thing, we're talking to her, then we're out to dinner with her.

"And I just thought, 'My God, is this thing happening?' And she took a character that we already loved, we really loved Pearl, and she made it so much better."

Melissa was overjoyed with the "smart" way in which Susan transformed the hard-drinking pensioner from "horrible" to "exciting".

She added: "She is such a smart actress. She's such a smart woman. But she's really so incredibly skilled at what she did, that she just played it with no judgment.

"She didn't see Pearl as this horrible woman that made all of these mistakes. She just thought, 'Well, everybody's got a past'. And she had a pretty exciting past. She kind of saw her as exciting, and it just felt right.

"The first day of shooting, I think it was at the screen test, when we finally had all of our wardrobe and hair and makeup on. We just looked at each other, and for whatever weird reason, everybody went, 'It just makes sense'."

'Tammy' is in cinemas now.