How do you know a social media phenomenon like the mannequin challenge has hit peak virality?

And it’s not even when LeBron James, Michelle Obama and the NBA champion Cleveland Cavaliers are doing it in the White House.

You know the mannequin challenge has reached absurd levels of cultural saturation when people imprisoned behind barbed wire —people under 24-hour surveillance, and denied access to smartphones — are pulling it off with aplomb.

That, as it turns out, is the case in Alabama, where a group of inmates managed to partake in the motionless online video challenge that has quickly become 2016’s version of the Harlem Shake.

The minute-long clip — posted on Facebook on Nov. 13, according to AL.com — relies on the disciplined cooperation of a several dozen freeze-framed inmates in white-colored prison attire labeled Alabama Department of Corrections.

No corrections officers can be seen in the video, but there is little doubt that inmates effectively conquered the “challenge” portion of the mannequin challenge.

Bob Horton, a spokesman for the Alabama Department of Corrections, told AL.com that the agency is trying to determine the source of the video. The news site reported that the location of the video shoot remains a mystery.

Being caught with an illegal phone in prison is not an infraction Alabama officials take lightly, AL.com reported, noting that using an illegal cellphone inside a state correctional facility is a Class C felony.

Since January, according to AL.com, “the ADOC has confiscated over 3,000 illegal cellphones.”

In the viral video, as the contraband camera drifts through the room, it captures inmates in various creative poses, from fighting (possibly with a real “shank”) to working out to reading scripture and praying to Allah.

The original post included the following message: “Free us… prison reform… free my family!” as well as several hashtags, including “#ALLlivesMATTER, #GodLovesAll, #ChaingangChallange.”

The video’s emergence followed riots earlier this year inside Holman Prison in Atmore, Ala., according to AL.com. Inmates who were able to contact the media during one of the riots said the violent protest stemmed from inhumane treatment, such as overcrowding, according to AL.com.

Though typically playful, the mannequin challenge has also been used to explore themes like police brutality and surviving as a person of color in America.

A one-minute mannequin challenge video released by comedian and writer Simone Shepherd is set to audio from 911 phone calls from the deaths of Philando Castile and Trayvon Martin and has been shared tens of thousands of times.

As The Washington Post’s Des Bieler reported, the challenge’s patient zero has been traced back to a random group of high school kids.

It quickly became a sports challenge that was picked up by everyone from kids to professional athletes.

“According to Mashable, the first #Mannequinchallenge was thrown down by a group of high school students, and already there are countless versions by other teens,” Bieler wrote. “Sticking with football teams (above the high school level), we also had fine examples recently by Navy, Michigan, Old Dominion and the Steelers. Even an SEC Network panel, including Tim Tebow and Paul Finebaum, at the site of Florida-Arkansas game saw fit to bring everything to a halt.”

The challenge’s unofficial soundtrack is the song “Black Beatles” from the Mississippi hip-hop group Rae Sremmurd, which unveiled its own version of the challenge this month.

The song hit No. 1 on the Billboard singles chart this week and the video challenge was even endorsed by one of the original Beatles.

MORE READING: