Zack Freedman has complete control and feels a sense of calm on the high wire. If only he could say the same about the rest of his life. His fellow youth circus performer and roommate, Cubby, hates him, and his aunt dumps a yappy, excitable dog on him. When a necklace is stolen during a circus performance and the victim of the theft threatens to shut down the circus, Zack is desperate to solve the mystery so he can keep his place on the wire.
Trevor, Nick and Robyn are ready to solve another mystery. When bobsledder Josh Gantz is accused of deliberately injuring a fellow competitor, he runs the risk of being thrown out of the sport -- right before the World Cup. Courtney Gantz asks Trevor, Nick and Robyn to help clear her brother's name. Can they find out who framed Josh? What is the meaning of the strange coded messages they keep finding around Olympic Park? Who eats orange bananas, anyway? The kids must unearth the clues in a race against time, before Josh's championship dreams end up on ice.
While volunteering at the local zoo, Robyn, Nick and Trevor learn that grizzly bears are being poached and their gall bladders removed for use in alternative medicine. Always ready to solve a mystery, the kids set out to find the poachers. Bear is not only big game, they learn, but big money to poachers. The stakes are high and the suspects many, as the kids head into their most dangerous adventure yet.
When Trevor, Nick and Robyn visit the Royal Tyrrell Museum, Robyn is inspired to raise funds for a dinosaur dig that will close soon if it doesn't find funding. The kids are caught up in another mystery when a chain of suspicious events, including the disappearance of important fossils and a fraudulent discovery at the dig, leads them to wonder what's going on. Is the new visiting scientist behind the fraud, or did Robyn's enthusiasm to save the dig lead her astray?
Trevor, Robyn and Nick decide they have a mystery to solve when Trevor discovers a suspicious looking young man snooping around. They learn about missing research involving the use of carob beans to aid in cancer treatment-potentially valuable information. With a shady looking grad student, a bitter activist and an employee of a medical research firm to deal with, our amateur sleuths are faced with their greatest challenge yet.
Would-be detectives Trevor, Nick and Robyn are hot on the trail of a sandwich thief when they learn that more than food has been going missing at school. A valuable hockey book has been stolen from the library, and the kids worry that the librarian might lose her job if it isn't found. Who would steal a hockey book? Could it be Robyn's arch-nemesis and hockey enthusiast Cray? Or could it be Ms. Thorson, the Oiler fan teacher? The kids are determined to solve these mysteries even though their sleuthing efforts land them into trouble at every turn.
Clay would much rather work as a lifeguard at the beach than at Safari Splash, the new water park in town. He's certain the summer will drag along, despite his position at the Boa, the park's fastest slide. The summer job starts to get interesting when he learns that someone has been wandering the park in a lynx costume, scaring the staff. When forty thousand dollars is stolen from the till, and his friends are under suspicion for the theft, boring is starting to look good. But Clay is certain that the mask and the thefts are connected, and he's determined to solve the crime.