The story will follow the network's two previous movies about the couple: 2018's "Harry & Meghan: A Royal Romance" and 2019's "Harry & Meghan: Becoming Royal."
The network said that "Escaping the Palace" would reveal what happened within the royal family that drove Harry, 39, and Markle, 39, to recuse themselves from their royal duties and relocate to America with their son Archie.
Specifically, the movie will chronicle Markle's isolation in the U.K. and the couple's frustrations at the lack of support in combatting intense media pressure.
Production is set to begin this spring with a debut expected later this year. Casting is currently underway. The previous two installments used largely different casts, including its two leads.
"Harry & Meghan: Escaping The Palace" is executive produced by Merideth Finn and Michele Weiss. Scarlett Lacey will write the script and Menhaj Huda will direct.
Reps for Markle and Harry did not immediately respond to Fox News' request for comment.
News of the Lifetime movie comes just weeks after the couple's bombshell interview with Oprah Winfrey, in which they detailed their reasons for leaving royal life behind.
During the tell-all, the two made several serious allegations against the royal family and the Institution at large, including accusations of racism and turning a blind eye to Markle's mental health needs.
They also discussed the media's presence in their life, reporting on their every move and the criticism of Markle's actions, which led to, in part, her suicidal thoughts.