The five remaining teams receive a clue in Ethiopia telling them to travel by a charter flight to Addis Ababa and then make their way to the Ethiopian stadium. Once there, all teams take part in a four-person relay race, teaming up with pairs of Ethiopian runners. Next, the teams make their way to Colombo in Sri Lanka, 3,600 miles away. There, the teams make their way by tuk tuk to their next clue where they encounter a Detour - "Tree Trunks" or "Elephant Trunks." Most teams complete "Tree Trunks" which involves climbing and careful balancing. The "Elephant Trunks" task requires patience while playing croquet and riding on an elephant. Once completed, the teams make their way to Kandi and from there, a clue tells them to make their way to Lion Rock. In this Roadblock, one person must climb a thousand steps to the top of a mountain and then use binoculars to search for the location of the next Pit Stop.

After another very unfortunate mistake, one team is eliminated from the race, leaving only four remaining.

Wanting to make peace with Rory, Christopher shows up at Yale, but she brushes off his attempt at reconciliation. When Lorelai learns that Christopher's father passed away, she spends an evening at his place trying to console him, then neglects to tell Luke the truth about where she was. Meanwhile, Emily and Richard are briefly reconciled when they take in a lost dog. Finally, Luke brings Lorelai her own portable skating pond, and the Stars Hollow annual Revolutionary War reenactment takes on a racy new twist.

When a high school student falls victim to a mysterious but lethal poisoning, House and his team jump in to find out what is killing the teen. Given a low heart rate and a clean tox screen, House sends Cameron and Foreman to the teen's home to find the hot new drug House is sure he's taking. They don't find any drugs, but think they've come up with the answers, until a second unrelated student is admitted with identical symptoms. With the boys' lives hanging in the balance, House and the team have to connect the dots fast. Meanwhile, an 82-year-old patient has become enamored with House while he helps her figure out the basis of her renewed fascination with her sexual feelings.

Continuing with the auditions for season 4 from New Orleans, Louisiana.

A man injured in a bar fight teaches Turk and J.D. a lesson about living life to the fullest.

Dr. Cox and Jordan have different opinions on having another child or not.

To make Cheryl feel desirable, Jim fakes a jealous rage in a restaurant and tries to teach Dana's date to do the same, but the lesson backfires when Dana fears her new beau is paranoid and possessive.

Haley is surprised when her older sister Taylor comes to town, but not as shocked as Nathan, who recognizes Taylor from a past tryst. Brooke and Felix decide to become an official couple. Jake makes a special visit to Peyton. Anna tells Lucas a shocking secret.

When the body of a seven-year-old child is found, the squad again begins to investigate convicted serial killer Lucas Biggs, believing that he molested and murdered the boy. While Biggs can detail every child he ever molested, he swears that he has no memory of this one. Further investigations show that there is another suspect, but before he can be picked up, someone picks him off.

Coming Soon...

TONIGHT: Author of "Chain of Command: The Road from 9/11 to Abu Ghraib", Seymour Hersh!