KINGSTON, ON - When three local filmmakers set out to make their first feature-length movie, they decided to shoot it all in a single take to add to its authenticity.

They didn't anticipate that their stylistic choice would earn them a Guinness World Record.

The film, 21 Brothers, tells the story of southeastern Ontario's 21st Battalion as it prepares for the First World War battle at Courcelette.

At 91 minutes, 21 Brothers has been recognized by Guinness as the longest single-shot film ever made.

Director and executive producer Michael McGuire grew up locally, as did the film's writer-producer Clayton Garrett and its cinematographer-producer Clint Tippin.

They shot the film three times in its entirety over one weekend in Elginburg in April 2011.

Although 21 Brothers falls under the genre of historical fiction, certain characters and situations were inspired by members of the 21st Battalion.

Garrett said he incorporated anecdotes he heard from members of his own family into the screenplay, as well as the stories of people he met during months of research.

Early in the writing process, Garrett conceived a story about a young man who lies about his age in order to enter the war.

During a tour of the Princess of Wales Own Regiment museum, Garrett was surprised to hear then-curator and retired Chief Warrant Officer Bob Pollitt tell him a family story that echoed his own fictional creation.

"He starts telling us about his father," Garrett said. "He was 14, he'd lied about his age to get into the war and they put him on the front lines. He starts telling back this whole that we'd been writing, verbatim."

McGuire, Tippin and Garrett said historical accuracy and approval from veterans were among their main concerns in creating the film, but breaking a world record is a nice bonus.

"We didn't even realize until about a week after we'd shot it that we were a minute longer than the previous record," McGuire said, adding it was a crew member who tipped them off.