Producers of the documentary “The Unknowns” have set a Memorial Day launch through the Gathr on-demand theatrical releasing operation, Variety has learned exclusively.

“The Unknowns” follows the training of the Sentinels at the Tomb of the Unknowns monument dedicated to American service members who have died without their remains being identified. A single unidentified U.S. serviceman who died in France during World War I was interred at the monument in 1921 in Arlington National Cemetery in Virginia.

The film was produced by U.S. Army veterans Ethan Morse and Neal Schrodetzki — both who served as Sentinels — along with Matthew Little. Mark Joseph (“Max Rose”) is the executive producer.

Because of the two veterans’ experience of serving at the Tomb, they were given an “unprecedented” level of access from the US Army, allowing them to bring a unique perspective to the rigorous and intricate training process that soldiers must endure to be stationed there.

“Our fans have been waiting a long time to watch the film,” said Morse. “I’m so excited to finally be able to announce our first distribution deal. We hope families all across the country will come together this Memorial Day to honor those that have given everything for our country.”

Schrodetzki said the Army gave the production access to training areas and routines that had never been filmed before. “Thanks to their trust and guidance, we were able to capture and recreate how it feels to be a new soldier taking on the training cycle,” he added.

Gathr began offering on-demand theatrical screenings this week.

“We are honored to partner with a film that pays respect to those who served in the armed forces like ‘The Unknowns,'” said Gathr CEO Scott Glosserman. “Its subject matter and presentation are of great importance to American society. Providing individuals across the country the ability to screen the film at their local movie theaters in time for Memorial Day creates an important opportunity for communities to come together to appreciate those who guard the Tomb of the Unknown Soldier.”

In the last 12 months, Gathr has held over 1,500 audience-driven screenings of over 40 different films. Some of its more successful releases have included “Girl Rising” with 964 screenings and a box office of $1.7 million and historical drama “Beyond The Mask” with 673 screenings and a $1.2 million gross.

“Girl Rising” told of the struggles of nine girls from nine countries. Narration was provided by Anne Hathaway, Cate Blanchett, Selena Gomez, Liam Neeson, Priyanka Chopra, Chloë Grace Moretz, Freida Pinto, Salma Hayek, Meryl Streep, Alicia Keys and Kerry Washington.