In an attempt to escape their stressful lives, four friends decide to play in a Seattle wedding band. The lead singer, Tommy, finds out that his ex-girlfriend wants the band to play at her wedding.
When Tommy's band plays at a Comic-Con event, an actress falls for him. Meanwhile, two nerdy high-school kids want the band to play at a party.
Tommy is stuck with babysitting Eddie's children. While he attends Rachel's fiancé's bachelor party, Tommy runs into his arch-enemy, who happens to be the best man.
Rutherford has to deal with her high-school arch-enemy as she plans an adult prom. Stevie is seeing a florist with kinky activities.
When Courtney Love's band steals some instruments, Tommy tries to get it back. Tommy's band butts heads with a boy band.
Tommy receives a surprise visit from his ladies' man father, who's panning his sixth marriage. Rutherford is working hard to arrange a complicated wedding.
Eddie is in a tight spot after he finds out that the band is playing at a corporate event where he works, and his work rival finds out that he's playing in a band.
After Tommy's band is hired to play at a divorce party, they end up getting the separating couple back together.
After a rock star hangs out with the band, they struggle to keep him from getting out of control, as he joins them while performing at a Sweet 16 party.
As tension rises between the band and Roxie, they work with her event-planner rival and they perform at an "End of the World" party. Roxie responds by hiring the band's rivals who perform at another themed event.