Three-time Oscar nominee Sigourney Weaver's next film project won't be on the big screen. Unless you have a really large TV set.

The "Gorillas in the Mist" and "Aliens" star will take the lead role and co-produce a film for Lifetime called "Prayers for Bobby." She'll play Mary Griffith, a woman who initially rejects her son's homosexuality, then becomes an advocate for gay rights after his death.

"Sigourney Weaver's passion and dedication to this project are incredibly inspiring," says Tanya Lopez, Lifetime's head of original movies. "As both the star and co-producer of this movie, she wholly embodies the strength and perseverance of Mary Griffith."

Based on Leroy Aarons' book, "Prayers for Bobby" centers on Mary Griffith, a devout Presbyterian who raises her children in strict accordance with church teachings. But when her son Bobby confesses he might be gay, she won't accept it and instead urges him to pray more and seek out a "cure." Bobby obeys, but he also spirals into depression and eventually commits suicide.

The film will also chart Mary Griffith's reaching out to the gay community, where she finds unexpected support.

Lifetime says "Prayers for Bobby" will be Weaver's first made-for-TV movie. Her past TV work includes the 1977 miniseries "The Best of Families" and 1997's "Snow White: A Tale of Terror," for which she earned an Emmy nomination. That film was originally intended for theatrical release but had its American premiere on Showtime.

Her film credits also include "Working Girl," "Tadpole," "Vantage Point" and "Baby Mama."

Katie Ford ("Miss Congeniality") wrote the script for "Prayers for Bobby," which is scheduled to debut in February. Russell Mulcahy ("Queer As Folk") will direct.