Nancy Drew and her friends Bess and George have been invited to tour the new Bio-Dome Eco-Park prior to its grand opening. Carson Drew, Nancy’s father, is the lawyer for Cheri Goale, the inventor behind the new park. As Nancy and her friends are enjoying the tour, Nancy recognizes a man that she once came into contact with on a prior case. Thinking the man is still up to no good, Nancy decides to keep a close eye on him. When a substance causes one of the domes to collapse, Nancy is positive she knows the culprit. Can she solve the mystery in time to save the remaining domes?