Julia Stiles says Jennifer Lopez was "very, very disciplined" on the set of 'Hustlers'.
The 'Save The Last Dance' actress plays the part of a journalist who closes in on Jennifer's alter ego Ramona and her stripper pals - who are played by the likes of Cardi B and Constance Wu - who carry out a series of crimes to seek revenge on their Wall Street clients.
And the 38-year-old star has revealed how her co-star was extremely professional in rehearsals.
Speaking to InStyle magazine, Julia said: "She's very, very disciplined.
"[Jennifer] was handed a full page monologue my first day shooting with her and she just read it a few times, closed her eyes, and then opened them and was like, OK, let's go.'"
The '10 Things I Hate About You' star also discussed how female characters who have behaved immorally always get judged "a lot more harshly" than men do.
She explained: "We judge female characters a lot more harshly, and if you have a female character doing something questionable, immoral, illegal, or unlikable, I find that storytellers have to jump through hoops to explain why she did that.
"If a male character's running around with a gun, it's cool, but if a woman is doing it, we have to have seen her suffer some horrible tragedy in order to justify it."
Meanwhile, whilst Jennifer, 50, might be a pro on screen, she previously admitted she was scared of taking on the stripper role because she is "exposing" herself more "emotionally and physically" than ever before.
She said: "It's a nightmare thinking about being up there.
"I'm exposing myself let's say - emotionally and physically more than I've ever done in a movie.
"And I've done love scenes and this and that, whatever, but not like I was up there like that."