When four popular high school girls play an evil prank on Reese by pretending he has a secret admirer and then dropping a pig off at his front door, Lois comes to his rescue. She plots her revenge on the four unsuspecting girls and wreaks havoc on their adolescent lives. Meanwhile, Hal realizes Lois is at a dangerous emotional place so he decides to get some distance and stumbles upon the idea for making his own pitching machine out of stuff in the garage.

After a self-imposed exile to China, David Sandström is kidnapped by the People's Liberation Army and ordered to secretly investigate a deadly outbreak that has killed 19 people in a small village. With the help of three Chinese scientists, David discovers the outbreak has been caused by an ancient bacterium that has seeped into the village's water system. David is horrified when he learns that one of the scientists has decided to test the antidote on her self in order to expedite a cure.

While David makes his way back to Canada, Caroline and Carlos are witness to a horrific attack at the site of the International AIDS Conference.

The family is at a church fund-raiser, where Homer tries to ensure his rubber duck onto victory, but Flanders wins the big prize, which he doesnt want and gives it to Marge. In return Marge agrees to watch Rod and Todd while Ned is attending a left-handed convention. While Marge is spending all her time with the Rod and Todd and trying to let them learn how to be boys; Homer takes Bart and Lisa to a home for former celebrity animals and a monkey kidnaps Bart. Marges ability to be a mother comes into question when Ned discovers what she is doing with his boys and the local news covers Barts current predicament.

When Bobby attends the school's job shadow program, he winds up interning for Peter Sterling, a man who runs a pooper-scooper business. Bobby is so impressed by Peter that he decides to pursue the same career. Meanwhile, Hank is trying to train Joseph at Strickland Propane.

While Bill seeks protection against the religious compound led by Roman Grant, things heat up between the sister-wives over Margene's overtly sexual behavior. Roman "The Prophet" asks Bill's father to act as a go-between to deliver a message to his son, and the Hendricksons get together for a family dinner with Bill's business partner and his three wives. Meanwhile, Margene pressures Bill about buying her a car and Ben goes out on a date with a girl that seems too mature for him.

Lilly and the cold case team will have to decode the clues given by a twisted killer in order to save the life of a young boy who has been left to die alone. But first they must find the boy and for that they need to dig a little deeper into their own pasts.

With Massachusetts suffering from a devastating wildfire, six firefighters perish in the blaze. Macy, Jordan and Nigel discover that these brave men should never have died and begin investigating whether they were murdered and, if so, who is to blame. Despite hitting a snag in their new romance, Woody and Lu work together to solve the mysterious death of an unidentified man in a superhero suit, which inevitably closes the distance between them and places them back on track. Meanwhile, Macy is torn about what to do when his daughter Abby threatens to leave rehab.

After a series of deaths at the hospital some of the staff become very superstitious. Izzie worries about Denny and gets confronted by Alex. A patient with OCD drives Cristina crazy. Derek and Addison discuss their relationships with Meredith. Richard treats a friend from 17 years ago who reveals a secret about a dark time in his past that involves Ellis. George gets an earful about the women he's not talking to. Burke and Cristina argue about kicking George out.

Logan and Barek investigate after Secret Service Agent Paula Kendall is found dead in her home. Suspicion initially turns to the husband after detectives realize it took him eleven minutes after a first failed attempt to get in touch with 9-1-1, and their investigation leads them to her husband's role in a proposed Indian casino. Logan and Barek are especially interested when it turns out that the 'witness' Paula was supposed to be meeting that night had ties to a local politician, who also had ties to Kendall's husband.

After Dana's family treats the girls coldly, Alice is determined to arrange a special event to commemorate their friend. While Helena's lawsuit is resolved with a surprising outcome, Bette is willing to fight for Angelica's custody. Max lands a job, giving Jenny something to write about. Dealing with her grief, Shane is willing to make the ultimate commitment to Carmen. Finally, Lara arrives from Paris and is comforted by Alice.

Tony runs into some trouble on a business trip to the West Coast. Christopher decides to discuss terrorism with the FBI. Meanwhile, the New Jersey family ends up mourning the loss of another one of their associates.

As election day nears, the candidates begin to feel the strain of the campaign trail. Despite the lack of sleep and physical ailments, the candidates are forced to make difficult campaign choices. Things take an unexpected turn when Vinick finds an opportunity to hurt the Santos campaign.

Ruckus spreads the word of White Jesus after he is diagnosed with cancer. Meanwhile, Huey tries to save a friend from death row.

Simon Amstell steps into the host's chair for more pop-related mayhem. Regulars Phill Jupitus and Bill Bailey test their knowledge of all things musical, assisted by TV presenter Nick Knowles, Friday Hill's Kenzie, comedian Russell Howard and Aaron Gilbert from indie band Delays.