Holly McCaffrey is putting on a show at the Merriam Theater.

It all started when the 21-year-old Marlton resident and Moore College of Art and Design senior got a chance to come up with a fresh take on the costumes for Mamma Mia!

That indestructible, irresistibly tuneful, ABBA-inspired musical returns to Philly on Tuesday and runs through Saturday at the Merriam.

And during the run, McCaffrey's illustrations for a sleek, less flamboyant, but still groovy trio of ensembles for the show's "Donna and the Dynamos" segments will be exhibited in the lobby.

"We love Holly's creations," says Crystal Brewe, a vice president at the Kimmel Center for the Performing Arts. The Merriam is a Kimmel venue.

"Rather than have Holly draw pictures of the actual costumes [that were] created in 1999, we invited her to use her creativity and imagination to draw images that depict what Mamma Mia! costumes might look like today," Brewe says.

"We love her interpretation and can't wait to share them with our audiences."

A longtime musical-theater and movie fan, McCaffrey grew up in South Jersey as a big fan of costume designer Colleen Atwood's work with director Tim Burton in films such as Edward Scissorhands and Ed Wood.

She began to take sewing lessons at 13. She also took drawing classes at the Perkins Center for the Arts in Moorestown.

Later, as a Cherokee Regional student, McCaffrey helped design costumes for the school's production of Annie.

She helped steam, press, repair and fit costumes for the cast of Death House, a horror movie being shot in Northeast Philly, as a Moore intern last spring.

And over the summer, McCaffrey had an internship with Lisa Zinni, associate costume designer for the recent Broadway production of An American in Paris.

The gig gave her a front-row seat as Zinni created costumes for the show's touring version.

"When you're designing a costume, you're trying to bring a character to life through wardrobe," McCaffrey explains.

Unlike with film or TV, she adds, a stage costume must "read," or communicate, from a distance as well as up close.

Authenticity matters as well, and McCaffrey researched the inimitable look that ABBA made globally famous during their 1970s heyday.

"But the source [material] for Mamma Mia! is really the music," she observes.

No problem: McCaffrey loves ABBA (as do I). She also shared her father's appreciation for the hit film version of Mamma Mia!

"When my dad was sick, he downloaded the movie to his phone," she recalls. "Mamma Mia!, West Side Story and Grease were his favorite musicals, but while he was sick, he always had Mamma Mia going."

Andrew McCaffrey succumbed to cancer at 51 on Oct. 29. A month later, his daughter was given the opportunity to update costume designs for his beloved musical.

"We have had an ongoing relationship with the Kimmel for a number of years," says Mellany Armstrong, Moore's assistant director of communications.

"Holly was recommended by [professor of fashion design] Janice Lewis."

Despite the crunch of finals and the tight frame - illustrations were due within a couple weeks - "there was more of a reason to take on the project, because my dad had passed away," says McCaffrey.

"Holly was the perfect person," Lewis says. "She has been committed to becoming a costume designer since I met her three years ago."

Indeed: McCaffrey is jazzed to be part of "the creative workings" of a show, whether onstage or on the screen.

"I like to present something to people and have them go, 'Wow,' like it happened to me with Colleen Atwood's work when I was a kid," she adds.

McCaffrey hopes to land a costuming gig with Saturday Night Live after graduation.

After all, she never imagined she'd get a chance to update costumes for her dad's favorite musical either.

And when I ask McCaffrey to name her favorite ABBA song, she doesn't hesitate before making the perfect choice: "Take a Chance on Me."