20th Century Fox, Chernin Entertainment and Paul Feig have launched development of a comedy spinoff movie based on Feig’s summer comedy, “The Heat.”

The untitled project will center around the characters Beth and Gina — played by Jamie Denbo and Jessica Chaffin — who were part of the raucous extended family of Melissa McCarthy’s Mullins character. The two women memorably grilled Sandra Bullock’s uptight Ashburn character in the film.

“The Heat” was a major success, with $230 million in worldwide grosses for Fox and Feig, who directed. The spinoff will be produced by Feig through his Fox-based Feigco along with Jessie Henderson and Chernin Entertainment, which produced the first movie.

Tricia McAlpin is writing the script.

Feig and his spouse Laurie have teamed previously with Denbo and Chaffin and produced six episodes of a “Ronna and Beverly” talk show.

Denbo sold a “Wedding Dance” pitch to Universal Pictures and has “Best Buds” with Natalie Portman attached at Vendome Pictures. Chaffin has a recurring role on the Fox series “New Girl.”

Denbo is repped by Apostle’s George Heller and Pakula/King & Associate. Chaffin is repped by CAA, the Schiff Company and attorney Jeff Endlich.

Deadline Hollywood first reported the news.