Darby Risner had worn the Barney head before, in seventh grade for a character dress-up day at school, back when the fuzzy purple dinosaur costume still had its full matching suit, before the arms on her scrawny teenage body grew just a bit too buff.

So when the 15-year-old from Alabama saw the dopey looking mascot head Sunday night, propped on the floor of her friend’s home, she plotted the perfect sleepover prank.

All alone, Darby lifted the plum, rotund head above her own and let it swallow her petite, 95-pound frame. Then she waited for the thuds of her girlfriends’ feet. When they tumbled down the stairs and rounded the corner, they found Darby as Barney.

“I didn’t scare them at all,” she told The Washington Post. “They just laughed.”

The giggling girls stood for awhile, then sat on the couch, Darby’s sandy brown hair still hidden beneath the big Barney head that had been the source of youth group entertainment for years at her church. The teen peered through the “Barney holes,” she said, to look at her phone, and with each movement the cartoon dinosaur’s neck hole slid further down her body. It inched past her shoulders and down to her elbows.

Fifteen minutes passed. The joke wore off. She was getting sweaty.

That’s when the panic set in.

Darby was very stuck.

Quickly, the tugging commenced, a handful of high school girls grabbing Darby’s feet and Barney’s head in a collective heave-ho.

Of course, as budding documentarians, the teens captured it all on Snapchat. Darby laughing. Darby wincing. Darby yowling and, like she always does, Darby making jokes.

“It’s hurting my upper arms,” she squealed in the middle of one futile tug. “And it took a long time to get these things big!”

“These things” were her now-buff biceps, attached to her rail of a teenage frame, and wedged inside Barney’s neck. After a year of lifting weights during her freshman lacrosse season, they had gotten “big.” And now they were impeding her freedom.

When the girls failed, they called on the mom of the house. When the mom of the house failed, they lubed up Darby’s arms with a slick coat of Vaseline. When the Vaseline failed, they called in the professionals.

On the other end of the phone, the local fire department told the girls that firefighters could head to the house for a rescue mission, but they’d have to do it officially — with the trucks, the lights, the wailing sirens.

Instead, the teens piled into a mini van. Barney rode shotgun.

When the gaggle filed into the station, well past 9 p.m., the firefighters inside fell into a fit of laughter.

“When they walked in, you couldn’t help but start laughing,” Trussville Fire Lt. Vince Bruno, a 33-year veteran, told AL.com. “We tried to be professional, and she was a little distraught, but we had to giggle about it.”

Then they started pulling too, but 95-pound Darby was so light their forceful tugs yanked her right off the ground. The Vaseline residue didn’t help matters. By now, Darby’s arms were so far absorbed she looked like an actual Tyrannosaurus Rex.

But finally, after a sweltering 45 minutes trapped inside, the firefighters snipped several small cuts at the base of Barney’s head. Darby was free.

Both arms were bruised. She was even sweatier. Her friends had already spread the word though every social media platform possible. Soon, the local TV news stations were calling. And the newspapers. Then came the national reporters. Even the Today Show.

“I honestly didn’t think it would accelerate this big,” Darby told The Washington Post.

The 15-year-old wasn’t prepared for Internet fame. She didn’t even have a Twitter account until this week. There, she searched “stuck in Barney” and found tweets from hundreds of strangers. On Instagram, she received numerous random follow requests. High school mascots have reached out in solidarity. There are memes.

Her friends have launched a campaign to get her on the Ellen DeGeneres Show, her lifelong dream.

As for her captor, the big Barney head has been returned to its owners, mostly damage free.

“It’s still wearable,” Darby said. “Just not by me.”

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