The comedy series kicked off season 2 on Wednesday.
The creator, writer and star of the ABC comedy told reporters during a live virtual panel at San Diego Comic-Con that viewers would be treated to a surprise cameo in the first episode of the season, vowing that "it's a really good one."
"It's someone we didn't think we'd be able to get," Brunson teased. "It's one of the biggest stars in the world to me. They are the biggest star we've seen thus far at Abbott Elementary."
The appearance lived up to the hype! Abbott kicked off its sophomore run with the most Philadelphia cameo of all time -- an appearance from the one and only Gritty himself.
The 7-foot-tall official mascot for the Philadelphia Flyers NHL team makes his debut as a special guest intended to surprise the students on their first day of school. But Janine (Brunson) mistakenly scheduled his visit for the teachers' first day of work, which is a whole week before students return to the elementary school. The incident is one in a list of many things that go wrong for Janine during the hectic development week, but the brief appearance by the lovable scamp of a mascot is the perfect way to introduce the 22-episode season.
During the Television Critics Association Summer Press Tour, Brunson called Gritty's appearance "the biggest celeb cameo of all time," sharing that the mascot is "very special" to the cast and crew as many are Philadelphia natives.
"Fun fact: we almost had Gritty for the pilot of our show. He's been invested from the beginning, before you guys even knew about the show," Brunson revealed. "So it was wonderful to get this opportunity to have him be involved. Gritty is just as vital to the particular Philadelphian spirit of this show as the Eagles are or cheesesteak or pretzels, etcetera. So getting him was like a dream come true. I was over the moon. I was starstruck."
Co-stars Tyler James Williams and Lisa Ann Walter wholeheartedly agreed, with the latter adding that the mascot is "undeniable. In person, he is even better."
Williams, whose Gregory doesn't initially seem to buy into the Gritty hype in the show, called the near-universal love for the mascot as a "phenom" that most people just understood.
"I feel like he relates to everybody on a human level, a cellular level. That doesn't need to be explained," he noted. "[He's] a true professional as well. Very professional."
Gritty is only the first of several guest stars in Abbott's second installment. Before the season premiere, ABC announced that the Emmy-winning series is rolling out a best-in-class guest roster, including Leslie Odom Jr., Lauren Weedman and Keyla Monterroso Mejia.
Odom Jr. will put his various talents to work as Draemond, the owner of a string of charter schools in the area who pays a visit to Abbott. Weedman is sure to get tongues wagging as Kristin Marie, a tough-talking teacher from a neighboring school who bears a striking resemblance to one of Abbott's own. On My Block's Mejia will guest star as Ashley, a teacher’s aide at Abbott Elementary whose go-with-the-flow personality contributes to classroom chaos.
Fans can keep watching to see if anything tops Gritty when Abbott Elementary airs on Wednesdays.