Bradley Cooper was asked to cameo in 'Dungeons and Dragons: Honor Among Thieves' "on a lark".
The 'Silver Linings Playbook' actor previously worked with John Francis Daley - who co-directed the film with Jonathan Goldstein - on short-lived TV series 'Kitchen Confidential' and had stayed in touch, and the Oscar-winning star "really responded" when his pal showed him a rough cut of the movie and agreed to make a brief appearance as the pint-sized Marlamin, the former husband of warrior Holga (Michelle Rodriguez).
John told Entertainment Weekly: "I asked him on a lark if he would be game to come and spend a day with us.
"We sent him a rough cut of the film and fortunately he really responded to it."
An early cut of the film showed actor-and-director Dexter Fletcher in the role, which the directors explained was done as a favour because of COVID-19 restrictions during filming, but the paid had always wanted someone highly recognisable to play the part.
Jonathan said: "Anybody who was willing to come to work with us had to endure a quarantine in the UK. So it limited some of the choices we had.
"Dexter was a friend of the court and someone who we thought would be great, and he was kind enough to come and do the part."
John added: "He was great. It was a really sweet, touching scene, but our intention had always been to cast that role with someone who immediately, when they open the door, the audience gasps in recognition."
When the scene was reshot with Bradley - and a chair made "30 percent bigger" to highlight the difference in size between Marlamin and Holga - Michelle admitted his casting made the moment even funnier.
She said: "I felt like I dropped character for a second there and it was like a spoof on a spoof within the movie, and then we can go back to suspension of disbelief. 'Cause for a moment there I think everybody is not thinking about the character within the movie. They're just seeing Bradley Cooper, this iconic actor, celebrity on screen.
"And I thought that was kind of really funny. I noticed in the audience at Austin [for the film's SXSW premiere] we all were thrown aback for a minute there.
"It was really cute. It was funny. It was a funny moment."
Co-star Justice Smith added: "What I love about that scene is that it's hilarious, but it is also very sincere."
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