NEW YORK — Lifetime will make a movie about Shanann Watts and her two young daughters who were murdered one year ago by her husband, Chris Watts, it was announced Thursday.

People announced the movie and said it will be based on real-life events and taped confessions about the murders that rocked the Weld County town of Frederick and the state.

People said the movie, “The Chris Watts Story,” will show the months leading up to the murders.

The movie is expected to premiere in 2020. A public service announcement to stop violence against women will be shown after the movie.

The cast includes Sean Kleier (“Odd Mom Out”) as Chris Watts; Ashley Williams (“How I Met Your Mother”) as Shanann Watts; and Brooke Smith (“Bates Motel,” “Ray Donovan”) as FBI agent Tammy Lee.

Watts killed Shanann, who was 34 and 15 weeks pregnant at the time, and their children, 4-year-old Bella and 3-year-old Celeste, on Aug. 13, 2018.

Weld County prosecutors said Chris Watts strangled his wife, then drove her body, with the girls sleeping in the back, to an oil site where he worked and buried Shanann in a shallow grave.

RELATED: Full coverage of the murders of Shanann Watts and her daughters

He then smothered Celeste in the back of the truck and dumped her body into an oil tank.

He returned to smother Bella, who begged for her life, prosecutors said. Chris Watts then put her body into another oil tank.

At the time of the murders, Watts was having an affair with a co-worker, Nichol Kessinger, who cooperated with police.

When Shanann Watts and the girls were first reported missing, Chris Watts conducted several news interviews pleading for their return before his story with Frederick police and FBI investigators unraveled.

He pleaded guilty to the killings to avoid the death penalty. He is serving five life sentences without the possibility of parole at a Wisconsin prison.