One ‘doozy’ of a movie scene

ACTOR Tim Blake Nelson has only one scene in Guillermo del Toro’s upcoming movie “Nightmare Alley” as “Carny Boss” but promises it’s a doozy. “Guillermo said, ‘I wrote it for you,’ ” the “Watchmen” star told The Post’s Nicki Gostin at the premiere. “He said, ‘It’s one scene but it’s really good.’ I said, ‘You didn’t need to say it’s a good scene, I’m there,’ and it is a good scene!” Nelson laughed when asked if he felt like a phony traipsing the red carpet, saying, “I’m in the movie, I can go to the premiere!” Star Bradley Cooper was on hand, as well as his ex, Irina Shayk, although they arrived separately. When paps called for her to stand next to a Cooper poster, she tartly said: “Why would I do that?”