After many aborted attempts, Sean Campbell (Bruce Greenwood) has finally cleared his relentlessly busy schedule to take his son, Mac (Daniel Magder), on an oft-delayed trip to Disney World. Unfortunately, his bosses at Arctic Oil have other ideas. It seems that a helicopter carrying an extremely valuable drill bit has crashed into a remote Canadian lake and that Sean is the only person who can recover it. Mac, who believes his father places more importance on his work than on his son, is very unhappy about trading in Mickey and Goofy for a backwoods town with little to offer a young boy. Things change dramatically, however, when Mac not only hears tales of a mysterious lake monster named Mee-Shee but actually stumbles upon his hiding place in a secluded cavern. Mac is enormously excited, but none of the adults take him seriously. This includes his father, whose attempt to retrieve the equipment is being foiled by the evil Watkins (Charles Mesure) and his henchman, Mr. Snead (Joel Tobeck), who work for a rival oil company and will stop at nothing to retrieve the drill bit for themselves. Things don't look good for Sean on either a personal or professional level -- until Mee-Shee manages to change all that.