In perhaps the most horrifying moment in Three Billboards Outside Ebbing, Missouri — the seven-time Oscar-nominated drama from writer-director Martin McDonagh — Sam Rockwell’s brutish cop, Dixon, casually beats the pulp out of local advertising impresario Reed Welby (Caleb Landry Jones), the man who owns the titular signs, before tossing him through a second-story window.

It’s a shocking moment within the film’s story, about a grieving mother (Frances McDormand) who wages a publicity war against her local police force for not finding her daughter’s rapist and murderer. But it’s also a technical coup for the filmmakers, all captured in a single shot without one cut.

In a clip from the upcoming digital and Blu-ray release’s bonus features, you can get a behind-the-scenes look at how McDonagh and company executed the shot (watch exclusively above). It involved a stunt double, some swift stair work by Jones, and a truckload of cardboard.

“It’s a very violent, brutal scene,” explains director of photography Ben Davis. “And the violence is all the more believable because there are no cuts within the sequence to remind you that you’re watching a piece of fiction.”

In other words, they kept it real.

Three Billboards Outside Ebbing, Missouri will be available on Digital HD Feb. 13 and will be released on DVD and Blu-ray Feb. 27.

Watch: Woody Harrelson compares Martin McDonagh to the Coen brothers:

Read more on Yahoo Entertainment:

• How ‘Three Billboards,’ ‘Shape of Water’ have suddenly become the Oscar favorites

• Sam Rockwell on channeling American rage in ‘Three Billboards Outside Ebbing, Missouri’

• About that ending of ‘Three Billboards Outside Ebbing, Missouri’: Sam Rockwell and Martin McDonagh reveal their theories (spoilers!)