Location: TanzaniaThe Thornberrys are in Africa for the opening of a new chimpanzee sanctuary which will also be attended by Jane Goodall, famous for her work with primates. When Eliza meets her and introduces her to Darwin, Dr. Goodall tells her that she disapproves of domesticated chimps. Will Eliza be able to convince her that Darwin WANTS to stay with the Thornberrys? Meanwhile, when poachers trap Eliza and Darwin, will Dr. Goodall, Nigel and Marianne be able to rescue them?

When Eliza meets a group of temple monkeys, they con her into bringing all of her family's food. While Darwin tries to convince her otherwise, Eliza realizes that she's been duped and learns the value of Darwin's friendship.

Location: Quito, EcuadorBefore New Year's Eve, Debbie accidentally hurts fer father's feelings, and joins a couple of eccentric, 30's-era volcano chasers, Mitzi and Merrick Dash. Eliza goes after her to reclaim her friend, Santusa the Llama, and they all encounter a mudslide when the volcano erupts.

During a drought, Eliza is forbidden to assist the thirsty animals, but she breaks her promise when she sees a cheetah cub alone on the Savannah. Eliza and Darwin are saved by a timely thunderstorm when the cheetah mother tries to eat them.

Eliza is afraid to admit to her friend Ben that she doesn't know how to snowboard, just as a rutting ibex is afraid to stand up to another ibex.

When Eliza is told that ""Jake"" the turtle is the last one of his kind, she can't just let his species become another name on the extinction list. Enlisting help from other animals, she soon discovers ""Samantha"" and brings the two turtles together--blind date style. Eliza soon realizes that playing the role of cupid is not as easy as it seems.

Location: Masai Steppe, TanzaniaEliza and Tyler work together to help an aspiring Masai warrior earn the respect of his elders.

In the hope of winning the annual horse race, Eliza trades in her bungling trotter for a swift Thoroughbred.

Location: Zanzibar, TanzaniaDebbie and Tyler mistakenly trade the commvee for a dress at an island marketplace; Marianne and Nigel explore the Ngorongoro Crater.

Geographical Location: AlaskaAt the request of the foundation, teenage rocker Shane G. joins the Thornberrys during their stay in Alaska. Since Eliza and Debbie both have a crush on Shane, they both go exploring with Shane only to discover who thick-headed he really is.

When the Thornberrys visit the !Kung people, everyone is shocked to discover that Debbie can click-talk. No one is more surprised than Eliza, however, who is only ""cured"" of her jealousy by a !Kung healing ceremony.

Location: Okavango Swamp, BotswanaIt's April Fools day, and The Thornberrys are trying to outdo each other by way of April Fool's jokes. At first it's a lot of fun, but when Tyler and Eliza encounter some quicksand and a lion, will they learn not to cry wolf? Meanwhile, Nigel coaches Debbie for her Physical Education courses.

Eliza busts a young elephant out of a Kenyan game preserve, only to face predators and poachers who are out to get them.

Eliza finds a hero in a giraffe who can see distances with his height and warn others of approaching danger. However, to Eliza's dismay, the giraffe leaves the animals for his own needs. Only when Eliza herself is in danger does the giraffe return and realize his selfishness.

Eliza goes to desperate measures to help animals survive during tough times along the Skeleton Coast. Her good-will intentions, however, will soon cost her family their entire supply of holiday cheer--and their Christmas dinner!

When Donnie kidnaps an aye-aye for a pet, Eliza must return the ""bad luck"" omen to his home before the villagers hunt him down.

When Eliza ""accidentally"" reads Debbie's diary she learns that Debbie thinks she's an embarrassment of a sister. Debbie and Eliza have it out and learn the real truth about their relationship.

When Eliza tries to swim with the humpback whales, Darwin accidentally knocks Debbie's boombox into the ocean, which creates a distrubing noise and causes the whales to stop their ritual singing. Eliza attempts to set things right, but ends up getting arrested for violating the Marine Mammel Protection Act.

The Thornberrys are visited by the Foundation's head son, Tom, who splits up the Nigel and Marianne team. An over-zealous Tom treats Eliza like a child until he lands the Commvee in a raging river. Eliza's quick thinking prevails and she saves her family and wins Tom's respect.

Location: Kakadu National Park, Northern Territory, AustraliaThe Thornberrys meet an Australian family named the Gibsons when the Comvee runs out of gas. Eliza makes friends with the youngest member of the family named Bethany, who is in a wheelchair from cerebal palsy. The girls go land sailing and Bethany helps Eliza escape from a crocodile, but then get in an arguement when Bethany thinks Eliza is feeling sorry for her being disabled. Will the two new friends find a way to make up? Meanwhile, Nigel and Marianne play the Gibsons in a very competitive game of Tricky Trivia.

Eliza and Debbie embark on a dangerous trek in search of precious gemstones.

Eliza's cousin Tyler Tucker joins the Thornberrys for a four-week tour from Africa to the Amazon in search of exotic, endangered and mysterious animals.

The Thornberrys pay a visit to Nigel's parents in Scotland at Thornberry Hall right before Nigel is to be made a knight by the Queen of England. Once there, Nigel's mother, Cordelia, presses him to accept a tenured professorship at Oxford. The prospect of the family settling down upsets Eliza but thrills Debbie. Meanwhile, Eliza rushes to save some golden eagles from eating poisoned meat from a trapper.

When Eliza discovers a secret temple, a group of jaguars believe that she is their long lost queen. Thrilled with her new royal position, Eliza gets in over her head and must escape the avenging jaguars.

Eliza and Debbie's combined bungling sends the commvee careening down a mountain, where it lies mired in the mud. They come face to face with a menacing-looking, but quirky tribe of silverback gorillas, and they must work together to ""unstick"" the van.