Tommy's ex-girlfriend Sara (Bree Turner) shows up out of the blue with great news: she's getting married. Oh, and she needs a favor - her wedding band cancelled last minute and wants Mother of the Bride to take their place. Emotionally, this is a conflict for Tommy. To the rest of the band, it's their golden opportunity to impress Sara's wedding planner, Roxie Rutherford, whose premiere wedding and events firm handles every five-star event in Seattle.

When Mother of the Bride plays a wedding at ComiCon, Tommy's performance draws the attention of sci-fi babe Alexa Stone (guest star Megan Fox) of the hit television series Plutopia. When his confidence impresses two unpopular fan boys, they proposition Mother of the Bride to play a high-school party in hopes that the band will make them cool enough to lose their virginity before heading off to college.

Despite knowing better, Eddie is forced to enlist Tommy to watch his kids. Tommy's planned activities include rock-star class, miniature golf and of course, a bachelor party for Rachel's fiancé, Adam (guest star James Carpinello). She's also enlisted Tommy to keep an eye on Adam because she doesn't trust his best man, and Eddie is surprised to learn the best man is his co-worker and rival, Cooper (guest star Ryan Hansen).

Rutherford is hired to plan an adult prom by her high school nemesis, Vanessa (guest star Molly Sims). Meanwhile, Tommy starts dating every guy's fantasy girl, the one they call "The Snippeter" because her day job is picking the perfect 60-second snippet of every song for iTunes. And Stevie dates Violet (guest star Fiona Gubelman), Rutherford's florist who happens to have a special old-school sex move.

After learning Courtney Love and Hole are recording in Stevie's studio, Tommy convinces his band mate to take her instruments for a spin at their next event. But after a run-in with boy band-cover band Just'a Krush, Hole's instruments are stolen, and Tommy vows to recover the instruments before Courtney finds out. The trail leads to a confrontation at a charity auction Roxie's throwing for her personal cause: Keckinger's.

Tommy's father, Jack (guest star Gary Cole), a larger-than-life ladies man, is back in town. Usually that means a couple of nights of drinking and hell-raising. Only this time he's here to tell Tommy's he's getting married for the sixth time. To make sure he's not making another mistake, Tommy sets out to prove to his dad via temptation he's incapable of being a "one-woman" man. Meanwhile, Rutherford has a blogger (guest star Barry Watson) shadow her in hopes the story will help her compete with a rival wedding planner. Of course it's the same week a bride (guest star Rachel Blanchard), whose dream wedding Roxie's been planning, reveals she has everything picked out - except an actual groom.

Rutherford books Mother of the Bride to play the corporate event for a big new client: Crate & Crockery Kids. The problem It's where Eddie works, and his conservative boss, Hank (guest star Kurtwood Smith) doesn't know his up-and-coming vice president rocks out on weekends. Things get especially dicey when Hank asks Eddie to plan the event with his wife (guest star Wendy McLendon-Covey) and even worse when Eddie's office rival, Cooper, (guest star Ryan Hansen) discovers Eddie's secret.

Mother of the Bride is hired to play a divorce party, but there's a sentimental catch. The couple splitting up is the same couple that hired the band to play their first wedding. Determined to be "wedding whisperers" and keep the couple together, Tommy and the guys have to go rogue from Rutherford's event plan, even if it means losing their jobs.

While playing Oktoberfest, Mother of the Bride is approached by a fan, rock star Declan Horn (guest star James Marsters). Declan wants to hang out with them, but in a lesson of "never meet your idol", the band has to contain Declan after he lets his inner-rock animal out at their next event: a Sweet 16 party.

After a falling-out with Rutherford, the guys are recruited by Roxie's rival event planner - and former assistant - Emily Corgy (guest star Erinn Hayes) to play an "End of the World" party. The guys don't feel good about the career move after learning Tommy and Emily have started dating. Worlds collide when they learn the event they're scheduled to play has been double-booked with another "End of the World" party thrown by Rutherford. Even worse, it's headlined by Mother of the Bride's rival - the Def Leppard tribute band Armageddon It (fronted by guest star Ken Marino). It's a recipe for disaster.