While helping her classmate Mandy search for her missing Jack Russell terrier, Veronica stumbles onto a bigger mystery, which affects pets all over Neptune. Meanwhile, tensions mount in the Echolls family as Trina tries to convince the now-retired Aaron to take a part in her new boyfriend's independent movie. Later, Weevil is arrested for breaking into the Kane residence and taking something from Lilly's room.
House and his team battle to diagnose a pregnant patient's life-threatening illness, prompting her to make the most emotional decision of her life, and Vogler is determined to fire House.
Luke helps turn an old house into a museum. Lorelai says too much during an interview about the inn. Rory, Paris and Lane have boyfriend trouble.
Vic and Monica stake a deal with the DEA to shut down Mitchell's tar heroin operation. When the bust comes up empty, Vic's suspicions of Shane grow, until Shane proves himself by coming up with a key piece of evidence that reveals a large stash of tar being stored at a local church. Meanwhile, Dutch and Claudette's friendship continues to feel strain as they try to tie a young woman's murder to a suspected serial killer. Plus, Julien takes a stand against Monica's policy, then goes to David for support when she suggests he consider transferring out of Farmington.
Turk won't open up at couples therapy. Elliot refuses Dr. Cox's romantic advice, when a very attractive man saunters into the hospital. J.D. learns a lesson in humanity from a dying old woman. The Janitor accidently lets a bunch of rats run around Sacred Heart.
The office staff play a basketball game against the warehouse workers in which Jim shows off to impress Pam and upstage her fiancee who is on the opposing team.
Curtis brings in a suspect who has critical information about Marwan's next strike. Michelle orders Curtis to use harsh methods to interrogate the suspect, but things get complicated when Marwan sends a lawyer to defend his rights. Logan's advisors begin to worry as he continues to exhibit fear in the face of the ongoing terrorist threat.
Streaky programs Dogbot to help Krypto so he can have more time with Kevin.
After Amy spends an hour chatting with Ray while he is trying to watch the basketball game, he tells Robert that she talks to much, which of course, Robert repeats to Amy, leading to a confrontation between Ray and "Lady Chatterly."
On the morning of his Julliard audition in New York, Ephram makes plans to meet up with Madison (guest star Sarah Lancaster) for coffee where he finds out that she was pregnant with his child. This devastating revelation causes Ephram to make decisions that will alter the course of his life. Amy tries to figure out what this will do to her and Emphram's relationship. Meanwhile, Dr. Abbott counsels a man (guest star Chris Penn) whose son may die as a result of a hunting accident.
Horatio's life is changed forever when he learns important information about his deceased brother. Horatio must now figure out what to do with this information about his brother, Raymond, and whether or not to tell Yelina. Meanwhile, the team investigates when a woman is murdered at a crowded bar after she's approached by a female employee of a service that helps men pick-up women. Also, when Delko loses his badge after some reckless behavior and it's used in a crime, he must locate the badge before it's used again.
The boys get out of jail only to find that Cory and Trevor messed up again and they don't own the park after all. Ray is hooked on VLTs.
Dana is stunned when Alice requests a bold sexual favor from her. Burr Connor (guest star Tony Goldwyn) reveals a secret to Jenny. Jenny learns about Carmen's real feelings for Shane, Kit plans a romantic night for Benjamin, and Bette and Tina have an intimate encounter as they bond over their unborn baby.
Lynette learns that no good deed goes unpunished when she momentarily befriends the mean Mrs. McClusky. Susan's mother decides to try and jump start her and her daughter's love lives. Andrew talks to a priest about his feelings, and tells him of his shocking plans for his mother, Bree. Gabrielle has her credit card declined in an upscale restaurant, and Carlos sends Gabrielle a big message about what will happen if she leaves him.
Gob hides George Sr. while the model home's plumbing is checked; George Michael helps Ann protest Maeby's new movie; Tobias takes a liking to Kitty after Michael asks him to keep an eye on her.
Through Professor Frink's future machine, Bart and Lisa see their lives in the year 2013, where Bart steals Lisa's chances at going to an Ivy League school in order to impress a skater girl named Jenda while Homer (now separated from Marge and living in an underwater apartment) fights Krusty the Clown after Marge begins dating him.
Lois goes over to visit Ida, but gets unpleasantly surprised by the St. Grotus Day festival. Malcolm fails a music appreciation course, and reluctantly goes to Dewey for help. Reese and Hal secretly watch scary movies while Lois is not around, but it ends up revealing some unexpected secrets about both Reese and Hal.
While George is feeling a little less masculine because of the way Izzie and Meredith have been treating him (like a sister), Izzie is assigned to a patient about to loose all of his masculinity. Cristina, true to her competitive spirit, shows up early and assigns herself to an ill woman, who happens to have been Meredith's moms scrub nurse. Alex, meanwhile, is busying himself copying and pasting pictures of Izzie's racy magazine spread all over the interns' locker room. And while Meredith is trying to cope with her mother's Alzheimer's, Derek treats a patient who has managed to get nails stuck in his head.