John Popper shows the guys how sweet life could be as a full-time kids' band when he lands them a party for Gilbert Gottfried's son for $10,000. The band gets a taste of the rocker good life, Dina gets a taste of Harry's crazy side, and the insatiable Kitty gets yet another taste of David.

Following a gig, Paulie and David spend the night with some groupies. The following morning they oversleep and realize they might miss one of there most important shows, a kid's party for a record executive, that could give them a deal.

Working for John Popper ain't so beautiful. Despite the mad cash they're pulling, the boys aren't allowed to write their own music. While they drown their sorrows in moist brisket and barbequed ribs, Dina confronts Popper and pulls out all the stops to try and get them out of the deal. Strangely, Popper's not interested in her generous "offer" but he does provide an unexpected way out. The only catch? She needs to even the score between him and his old nemesis, Harry Braunstein, the man who's ready to make their lifelong dreams finally come true.

The boys get the big break they've been working for when they open for Joan Rivers. But with their confidence at an all-time high, they succumb to the temptations of the casino and jeopardize everything in the process. Paulie learns that alcohol does affect decision-making; Joey discovers that putting a Cassata-style "beating" on the casino can have consequences; and David proves he doesn't have to be in Brooklyn to do something stupid -- the Tri-State area works just fine.

Faced with having to accept the Popper deal or lose it forever, the boys decide they don't care if they lose it forever -- they'll never sacrifice ZO2 for money. And then they do. When they learn that Dina's lost everything trying to make their dreams come true, they put their dreams aside for her and agree to be Z Brothers exclusively in exchange for Popper's sweet contract cash. Of course, that's before they learn that Harry Braunstein has a spot for ZO2 on his roster after all.

The guys show up to a kids' party in Long Island and learn it's been double-booked. No problem, except for the fact the other band is Kidtastic! - their nemesis in the kiddie world. Joey seeks relief from those goofy bastards, Paulie seeks relief from a persistent rash, and David seeks relief from a persistent female admirer - Kitty Braunstein. In the end, all 3 of them get their "heads" examined.

While playing at a bris, the Z Brothers meet John Popper and gives him their CD. After listening to their music and with a little help from a friend, John Popper offers them a record deal.

Haunted and confused by his feelings for Paulie, Neil terminates ZO2's regular gig at Southpaw. With the future of the rock band in question, Dina lands them a gig at Manhattan's Cutting Room. Only it's jazz night, and the crowd doesn't dig their sound. The guys somehow dodge an all-out race war and win over the audience, Joan Rivers, and a tearful Neil in the process.

The boys make a music video with the help of rock star Dave Navarro. Fresh off the success of his first "feature" - a critically acclaimed adult film entitled, "Broken - Navarro's wildly ambitious vision puts the reputations of both ZO2 and Z Brothers at stake. When he quits the project to pursue another project, little brother Brian Z comes to the rescue.

The future of the band comes in question as Paulie begins to pursue his solo career, David tries out modeling and Joey tries to find himself. The guys must choose to either go their own way or if they'll continue on a path as a band.