When Zoey enrolls in Ted’s class, she manipulates his students into taking her side in the fight to save the building being torn down to make room for his project. Meanwhile, Marshall and Lily spot Robin marching in the Halloween parade of shame.
The case of a murder and missing person on a secure compound perplexes the CBI team.
Pierce and a few other Greendale students ingest a biohazard substance at the school Halloween Party, causing them to exhibit flu-like symptoms and begin turning into zombies. It is up to the rest of the gang to save themselves and the school when Dean Pelton locks them in with the zombie-infected student body.
Claire gives each family member a role to play in spookifying the Dunphy house for Halloween, but Cameron hates Halloween due to a traumatic childhood experience. Mitchell had a terrible day at work, and Gloria acts weird after Jay and Manny tease her about her accent.
Frankie is excited over being invited to an adult neighborhood Halloween party. But will she be able to get Mike to dress up in a costume, or will he have his own idea of fun? Meanwhile, a melancholy Sue’s spirits are lifted when she discovers that Reverend TimTom is back in town and hosting a Halloween church event; things don’t go quite as planned for Axl, his friends or their dates as they head out to an exclusive haunted house party; and Brick chooses a unique Halloween costume that is not easily defined.
Graystone Industries provides an opportunity to never lose a loved one thanks to breakthrough technology. Others are staring down the same path as the deceased when held at gunpoint, and even still others are doing the gun-holding against another life-force. What the frak will they do?
Alicia and the partners must decide whether to take on the case of a VIP massage therapist who accuses a Nobel Peace Prize winner of sexual assault. Peter and Eli try to figure out what Wendy’s candidacy means for their campaign.
When Scott’s team explores a new planet, a plant-like organism infects the lieutenant, causing him to hallucinate a life back on Earth where he is getting married.
When a beautiful woman is found dead in an alley, all clues point to her being a victim of the notorious Triple Killer. The Triple Killer, or 3XK, terrorized New York City four years ago, then mysteriously disappeared. Now he’s back. In a deadly battle of wits, Castle and Beckett race against time to stop 3XK before he claims his next victims.
Marshall and Lily try to figure out how to conceive a baby with the gender of their choice; Robin’s perky new co-anchor irritates her.