When I was sorting through party invitations pre-Sundance, I almost missed it. And then my eyes focused and realized I was being offered a chance to see Joan Jett — and the Blackhearts, thank you — perform a show at HarryO’s on Main Street Saturday night.

It quickly went straight to the top of the personal event list for the week. Not because I have remained a fan since 1981, but because it was a chance to see Joan Jett perform, for chrissakes. My first rock crush (also from my hometown of Philly). Like many contemporaries, “I Love Rock N’ Roll” was my first sing-along anthem (though Pat Benatar’s “Hell Is for Children” came right after), and she, along with Chrissie Hynde, represented the ultimate teenage fantasy: an attractive woman who could rock harder than you.

Anyway, the hour-plus show, which was a way to promote Sunday night’s premiere of “The Runaways,” about Jett’s first band, delivered and then some. HarryO’s was completely packed, and Jett pulverized it with her simple, crunchy chord progressions and aggressively sexual vocals.

Just short of 50 years old, she’s still got the ripped arms, the jet-black needles of hair, the fist pumps, the growls and moans. Jett stood, legs spread planted, wearing a gold spangly sleeveless shirt and strumming a black guitar with a heart cut into it.

She and her four-piece band rocked through the catalog: “Do You Want to Touch Me (Oh Yeah),” “Crimson and Clover,” “I Love Rock N’ Roll,” “Bad Reputation,” “I Hate Myself for Loving You,” the Runaways hits “Cherry Bomb,” “I Love Playin’ With Fire” and “School Days,” plus newer songs “Fetish,” “Androgynous,” “Naked” and “A.C.D.C.” She finished up her encore with a sing-songy, rock-and-roll version of Sly and the Family Stone’s “Everyday People.”

During a brief interlude, Jett made sure to plug the movie and give what were probably the least punk shout-outs from the stage she’s ever given to Bob Berney of Apparition, Bill Pohlad of River Road and producers Art and John Linson. Patrick Wachsberger of Summit Entertainment, which is releasing the movie internationally, was in the balcony, and his partner Rob Friedman was spotted outside the venue in a slick-looking, ribbed black North Face jacket presumably stuffed with thousand-dollar bills from “Twilight.”

At a second break, Jett brought former Runaways bandmate Cherie Currie on stage along with their acting foils Dakota Fanning and Kristen Stewart.

The most pointed moment came when Jett was encouraging a sing-along to a chorus and said: “Focus you power. Focus your power right here.” As she beckoned with both hands toward her body, guitar jutting out in front.

Done and done.