When Aang and his friends meet a professor who knows of a library that contains information about the world, Sokka decides to go there to try and find some information to use against the Fire Nation. The library is guarded by the knowledge spirit, Wan Shi Tong, who doesn't welcome humans into his library, because he believes they only seek information for evil purposes. When Wan Shi Tong discovers Sokka wasn't being truthful with him, he begins to sink the library, bringing the kids down with it. Will everyone be able to escape the library in time? And who are the strange benders who are trying to kidnap Appa?
Aang searches for Appa, while Katara struggles to keep everyone together so they can survive in the vast desert while Sokka supposedly gets "high" of Cactus juice in the desert. Meanwhile, Iroh and Zuko seek help from an ancient secret society. Will Aang find his furry friend or did the sandbenders cause a catastrophe?
Two Wraith Hive ships have captured Dr. McKay and Ronon and are on their way to Earth. It is up to Colonel Sheppard to rescue them and figure out a way to stop the Wraith from reaching a "new feeding ground".
The Whiskers family gets separated when they go out foraging for the first time since they became a party of 40. The rival Lazuli tribe continues to cause problems.
Gus believes he's reached his personal nirvana when he and Shawn are asked to help investigate the disappearance of an inhaler at the Regional Spelling Bee, but things turn deadly with the murder of the bee's spellmaster and only Gus' encyclopedic knowledge of the event can help Shawn solve the case.
