Kieran Culkin “panicked” his A Real Pain director and co-star Jesse Eisenberg by not knowing his lines when he turned up to set.

In the comedy-drama, which was written and directed by Eisenberg, the actors play American Jewish cousins Benji and David, who go on a tour of Poland to honour their late grandmother.

Culkin explained on the SmartLess podcast that he and Eisenberg had two very different approaches to the work – the Zombieland star was very prepared and had shot a mock version of the film on his phone while the Succession actor arrived on set in Poland not knowing his lines or the shooting schedule.

“He’s anxiety personified,” he joked of his director. “Nothing caused him more panic than me walking to set going, ‘What are we shooting today?’ And he’s like, ‘What?! No! There’s like a whole page-long speech, what’s wrong with you?’ I’m like, ‘I learn lines fast, don’t worry about it.’ And I don’t like to rehearse and I just sort of look over it really quickly and (I’m like), ‘Those are the lines… let’s go.'”

The 42-year-old revealed that Eisenberg eventually “abandoned” his shot list – which outlines all the shots he wanted to get for his film – because Culkin was such a big advocate for spontaneity and trying out ideas in front of the camera.

“He kind of abandoned it on like the second or third day,” he recalled. “He told the cinematographer, ‘Never mind, f**k the shot list, pick up the camera.'”

The former child star noted that he used to be “extremely prepared” with his lines but he had to adopt a “fly by the seat of my pants” approach while making Succession as he sometimes received re-written scripts on the day of shooting a particular scene.

A Real Pain will be released in U.K. cinemas on 10 January.

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