Sandra Bullock (L) and Melissa McCarthy attend 'The Heat' New York Premiere at Ziegfeld Theatre on June 23, 2013 in New York City

Sandra Bullock (L) and Melissa McCarthy attend ‘The Heat’ New York Premiere at Ziegfeld Theatre on June 23, 2013 in New York City

*Although Sandra Bullock won’t be joining the Will Smith/Jay-Z-produced “Annie” remake as Miss Hannigan, she’s still got three films confirmed for the next two years – including a sequel to her current movie that arrives in theaters this weekend.

Bullock stars opposite Melissa McCarthy in “The Heat,” a crime action comedy in which FBI Special Agent Sarah Ashburn (Bullock) and Detective Shannon Mullins (McCarthy) must overcome their irritation with each other to take down a Russian mobster.

Early reviews have mentioned the comedic chemistry between the two leads as being among the film’s strong points. “It was really easy for us to work together,” Bullock told us during interviews for the film.

Below, she explains their approach to delivering the funny in each scene – mixing a little bit of the script with a lot of improv.

“The Heat,” from “Bridesmaids” director Paul Feig, opens Friday (June 28). Watch the trailer below.