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...

Trevor has started his first job at Ashton's Fresh Marketplace, where someone has been tampering with the food. Cayenne has been sprinkled on cookies, garlic put in coffee, and plastic insects hidden in fruit displays to terrify customers. Trevor and his friends Nick and Robyn decide to find out who is out to destroy the store's reputation. Is it Mattie, the disgruntled ex-employee? Or perhaps the competition? Or is it Alex, their schoolmate who doesn't...

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 a 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.