In the Cameron Crowe-directed movie, Cooper plays a military contractor who returns to Hawaii for a big job. While trying to reconnect with an old girlfriend (Rachel McAdams), sparks start to fly between him and the watchdog (Stone) who has been assigned to him.
"I think it's an attempt at rejuvenating the romantic comedy genre," Cooper said. "I mean, that's sort of a place people stay away from these days because it's hard to make a good one and I think Cameron ran head first into it."
And Stone ran head first into learning how to play a couple of musical instruments for her role.
"At home, I fiddled around on that guitar a little bit," she said. "Someone came over and taught me some guitar and ukulele. That was pretty great."
And for all you film buffs who can't not think of Lauren Bacall when hearing Stone's beautiful raspy voice, we have a great story for you. When Stone was making Gangster Squad, she wanted to send flowers to the Hollywood icon for her birthday and to thank her for bing an inspiration for her role as an aspiring actress who is dating a mob boss (Sean Penn).
"One of the producers spoke to her and said, 'We have an actress who would love to send you flowers for your birthday. Her name is Emma Stone.' And she said, 'I don't who that is but tell her orchids—no cut flowers,'" Stone recalled. "Isn't that the best?...They don't make them like that anymore."
For more on working with Cameron Crowe, check out what Bradley and Emma had to say in the video below.