In a recent interview, Billy Corgan spoke about the fluid nature of Smashing Pumpkins' lineup these days and not getting caught up with who and who isn't in the band. But when you look onstage and see James Iha, the one former member that Corgan has most frequently traded barbs with, it's a pretty big deal. And that was the case Saturday night (March 26) in Los Angeles.

Smashing Pumpkins were continuing their "In Plainsong" tour in Los Angeles at The Theatre at the Ace Hotel when the surprise moment occurred. The audience went wild when Iha walked out and joined the group with guitar in hand. According to Alternative Nation, Corgan stated, "Yes, it's James Iha," adding that the guitarist would join the band for the Siamese Dream portion of the show. With original drummer Jimmy Chamberlin having rejoined the Smashing Pumpkins' lineup during the run, that made for three quarters of the original group onstage in one night, with bassist D'Arcy Wretzky being the lone absent member.

The lineup of Corgan, Iha, Chamberlin, guitarist Jeff Schroeder and touring members Katie Cole and Sierra Swan then rocked through such songs as "Mayonaise," (fan shot video above) "Soma," "Rocket," "Spaceboy," "Today," "Whir" and "Disarm."  For those wondering, Iha last performed with the band on Dec. 2, 2000 in Chicago.

The guitarist would return later in the night during the encore, first performing on a cover of the Rolling Stones' "Angie." Corgan then explained that it was Iha's birthday and serenading him with "Happy birthday" while providing him with a cake. Finishing out the set, the band performed "Amarinthine." The two then embraced before parting ways again.

Keep up with Smashing Pumpkins on tour at these locations.

Update: The band repeated a similar set with James Iha the next night  (March 27) at the same venue.

Watch Smashing Pumpkins With James Iha Perform "Today"

Watch Smashing Pumpkins With James Iha Perform Rolling Stones' "Angie"

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