A subway station gas attack, similar to one that took place in a Baltimore church five years earlier, brings Baltimore detectives Tim Bayliss and Frank Pembleton to New York to assist Briscoe and Curtis. This crossover continues on Homicide: Life on the Street S04E12 For God and Country (II).
After an argument with Shawn, Marlon decides it's time for him to claim his independence and move out. Marlon ends up rooming with White Mike, while Shawn takes in T.C. Unexpectedly, Mike and T.C. dump Shawn and Marlon as roommates, forcing them back together -- something we later discover was engineered by Pops, who wanted the boys to reconcile.
Gibby picks Martin to represent Whitestone at the Chicago Book Fair, informing him with one weeks notice. This means a ton of extra work and pregnant Toby doesn't really feel up to it, so Martin suggests they take on a temp to lighten the load. Toby offers up her cousin Louie, and although initially reluctant, Martin assents, giving him a trial period to prove himself.
Emily finds out about Charlie's affair and they break up. Kathleen tells him that she doesn't want to be just another girl, and wants to take their relationship ahead. Sarah is mad at Bailey because he didn't tell her about his college plans. Robin meets Sarah and tells her that she's leaving in two days. Sarah asks her to stay, and Robin gives Sarah her cat, promising that she'll be back. Claudia is trying to get closer to her grandpa, and she asks him to move into the house. Julia tells her how much their mother hated him for leaving her. Jake tells Julia that he wants to be a part of the family, and so she accepts him, thinking that their mother would have done the same. Jake moves in.
Worms, squid, clams, and flies are spineless creatures. They’re not afraid, they’re invertebrates – animals that don’t have backbones. Invertebrates are everywhere. You can find invertebrates in the sea, in freshwater, and on land. There are about 30 times more invertebrates than vertebrates on Earth.
When Tia and Tamera volunteer for community service at a retirement home, Tamera's charge Edgar (Berle) proves to be more than she can handle. Meanwhile, Ray's stint as a teacher turns into a snooze-fest for his students.
After decades of persistence, Emperor Pilaf finally steals the dragon balls and summons Shenron! But Pilaf slips up yet again and wishes Goku back to childhood size!. As Goku tries to present his new self to his family, King Kai reveals alarming news. If the dragon balls aren't returned to Earth within one year, the entire planet will explode!
Valerie's really annoying friend Ginger returns to town. She forces Val to put her up at a hotel and pay for room service and new dresses. Ginger blackmails Valerie, threatening to tell everyone about the previous fall's scam unless Val coughs up $50,000. She later changes her mind and demands a night with David instead. Clare and Donna confront Kelly after finding drugs in the apartment. She seeks refuge with Colin, and doesn't show for the girls' rummage sale. Brandon takes Kelly for a ride and refuses to drive her home until she has come to her senses. She steals his car when he pulls over to call Susan, then returns to the apartment and tells Donna that she is moving out. Brandon, Steve and Joe accept Jonathan's invitation to go flying in biplanes. Joe faints after his flight, prompting more concern about his heart. He agrees to another appointment with Dr. Martin.
The World Tourists team up with Dingo and Fox to stop an artificially intelligent machine mass undergoing a grey goo situation.
In Ireland, Goliath, Elisa, and Angela find themselves trapped by the Banshee, who believes they're agents of Oberon come to take her back to Avalon.
Hayden must confront his inept gardener when all the plants in the yard start to die; but when Hayden fires him, he gets a chilly reception from Luther, who thinks the daffy worker deserved a second chance.
Alien Rangers defends the Earth against Master Vile and his army of monsters.
Jill wants Tim to get a vasectomy when they agree their family is complete. Meanwhile, Randy is voted "best butt" by the girls at school.
Realizing that it's time he started dating again, Niles takes Daphne to a society ball.
While Nana Mary amuses Roseanne and Jackie with a box of their childhood treasures, Dan and his pals reluctantly play poker with Leon and Scott.
A bruised and battered wife tells Sipowicz that her husband claimed to have killed somebody 8 years previously. Sipowicz follows a trail, leading back to 2 previous relationships. Russell is told that her father has been shot and killed. Her brother claims to have done it, but Simone thinks he's not telling the whole truth.
Moesha turns 16, which means her father's ban on dating is over, and Ohagi siezes the opportunity despite warnings that she's "high maintenance."
A publicity disaster occurs when Antonio covers for the Hacketts so they can go to a hockey game. Antonio bumps the Bruins' abrasive star goalie Danny "Dead End" Connelly off a Sandpiper flight to a critical game, causing the Bruins to lose. Meanwhile, winter tourism on the island takes an upswing when Casey welcomes the International Society of Masochists to Nantucket.