The Mount Hebron High School graduate, who grew up in Ellicott City, landed several parts in the production, "Cassandra's Angel," which is now on a 20-city, 20-week nationwide tour that includes schools and other venues in the Baltimore-Washington area this month.
Local stops include Dogwood Elementary School on Monday and Woodlawn Middle School on Tuesday, both in Baltimore County.
Joining the production will be "Cassandra's Angel" creator Gina Otto, who spent 12 years in the television, film and fashion industry but left after being disenchanted by mass media's negative images of women and girls.
Otto wrote "Cassandra's Angel" and has since spent 15 years using it as a backdrop for motivational speeches worldwide. The production has also been the basis of a children's book.
The bus-tour production focuses on such topics as bullying and negative images, and encourages youngsters, particularly girls and young women, to realize their full potential.
"The core idea is that every person has a bright light inside of them," said Pfeifer, 24, who has been pursuing acting since taking part in a Mount Hebron production of "Godspell" in the ninth grade.
"Throughout your life, people will tell you stories about who they think you are, and if you start believing enough in those stories then your bright light tends to be put out and you will forget who you are truly meant to be," Pfeifer added. "'Cassandra's Angel' encourages people to let their bright light shine."
Pfeifer plays the lead character's mother, a schoolyard bully and her father's secretary.
"It's one of those [productions] where you get to do a lot of funny, different things and change your costume a lot," said Pfeifer, who graduated from Mount Hebron in 2004 and went on to earn a degree in music theater from Catholic University of America in Washington.
She has worked steadily to make her name in theater. She performed for the Bethesda-based company Imagination Stage and was part of a teen acting group called the Young Columbians that performed throughout the area.
Pfeifer was part of the cast of "Beauty and the Beast" at Toby's Dinner Theatre in Columbia and appeared in the stage play "Legally Blonde," produced by Gaithersburg-based theater production company Troika Entertainment.
"Even as a freshman, I could tell that she was special. She came in head and shoulders above her peers," Mount Hebron drama director Tom Sankey said of Pfeifer. "With 'Godspell,' she was so enthusiastic, so well- prepared, she lit up the stage with her audition. She continued to grow, and she's one of those people that you knew something special was going to happen to."
With "Cassandra's Angel," Pfeifer relishes the opportunity to inspire youngsters to pursue their goals, particularly those who are struggling with the self-doubt that comes with adolescence.
"I know that in going through my life, that has very much been something I experienced," she said. "I think every kid in middle school and early high school goes through a period where they really start to doubt themselves, and I think probably when most people look back on that part of their lives, they can identify with feeling that way.
"The idea to know yourself," she said, "and always be able to trust yourself and let that guide you through life — by doing that you will also end up changing other people's lives."