In part one of the two-part, two-night second season finale, Walter and Olivia travel to the parallel universe, and the anticipated face-off between Walter Bishop and William Bell occurs.

Frankie points out to Mike that his social ineptness has been passed on to Brick, leading Mike to decide that both he and Brick need to be more social, and the Heck family BBQ is the perfect time to try. Meanwhile, Axl volunteers to clean the family pool in an attempt to get girls to stop by and swim and Sue tries to raise money for a local parish because her new friend, Reverend TimTom might be leaving in order to keep costs down

After a violent attack on someone very close to Anna, she delivers a message that the Vs don’t feel safe and will be leaving while she also gives a list of possible Fifth Column members to Chad hoping he’ll investigate to help in finding them. Meanwhile, Erica and the team try to track down a scientist who may have created a weapon that the Visitors are afraid of.

A robbery-homicide prompts Beckett to invite Demming to assist on a case, giving Castle a ringside seat to their budding romance. When it becomes clear that the two men have very different ideas about how to proceed, the investigation becomes an unspoken competition for Beckett’s attention, one in which each man races to solve the case, as Beckett referees between her two admirers.

When Ted, Marshall, Lily and Barney crash a highfalutin party at a swanky New York apartment, Ted gets the chance to mingle with the snooty guests and show off his intellectual side.

The family waits for news about Hank. While Jesse covers at the lab, Walt attempts to placate Gus. After witnessing a disturbing outburst, Walt worries he and his family are in danger.

The sexual tension between Jeff and Britta becomes a hot topic in study group. A contest for a chance at early class registration turns the peaceful campus of Greendale Community College into an all-out war zone.

Peter teams up with a local law enforcement official, Sheriff Mathis, on a serial murder investigation with ties to Newton. Meanwhile, Walter copes with the possibility of being sent back to St. Claire’s, and someone from the « other side » pays a visit.

Mother’s Day for Frankie is anything but serene when she finds herself doing more for Mike and the kids and less for herself. But she learns that the apple doesn’t fall far from the tree when she escapes the family for a few hours to go to her mom’s (Marsha Mason, « The Goodbye Girl, » « Chapter Two ») and ends up acting like a child by making her mom wait on her hand-and-foot. Meanwhile, Sue feels guilty when she steals a motivational magnet from a store whose message actually enticed her to shoplift it.

The police are quickly at the door when Peter’s electronic monitor sounds after he chases Alicia out of the apartment. As a result, Grace and Zach scramble to figure out a way to keep him from being arrested.