Overture Films, making its first move into production, is partnering with Echo Lake Prods. on “105 Degrees and Rising,” set against the backdrop of the 1975 fall of Saigon.

Jon Amiel (“Entrapment”) is slated to direct William M. Akers’ script. Echo Lake’s Doug Mankoff, Mike Marcus and Andrew Spaulding are producing along with Rob Cowan (“De-Lovely”).

Echo Lake developed the project with Amiel and brought it to Overture, formed last fall under CEO Chris McGurk and chief operating officer Danny Rosett.

Overture plans an annual slate of up to a dozen features, with pricetags of $30 million or less and targeted to specific auds — while being able to tap into the resources of parents Starz and Liberty Media.

Akers’ script weaves together several storylines as characters struggle to escape South Vietnam during the final days of the U.S. control of Saigon. Title is based on a secret code broadcast on Armed Forces Radio, in which the announcement that “the temperature is 105 degrees and rising,” followed by eight bars of Bing Crosby’s “White Christmas,” meant all U.S. citizens should immediately evacuate Saigon.

Overture made its first acquisition during Sundance, picking up U.S. rights to “Ferris Wheel,” a drama about a young girl’s search for parental love that stars Charlize Theron. That film’s in post-production.