If it wasn’t for a disastrous, drunken show they performed as a favor to their friend Cameron Crowe, Pearl Jam wouldn’t be the band they are today.

That was one of the lessons learned Saturday afternoon at the Toronto International Film Festival — where “the hottest ticket at the festival,” according to doc programmer Thom Powers, was to the premiere of a documentary about a rock ‘n’ roll band whose name does not include the letter U or the number 2.

Powers said the distinction belonged to “Pearl Jam Twenty,” the Cameron Crowe-directed film that takes a 20-year emotional journey with the seminal Seattle band and its fans.