Air date: 6/27/1988

The generally uplifting Nicktoon (and European import) The World of David the Gnome took a dark turn at the end of the show's short run. In the finale, viewers learned that even though they'd only known David for two seasons, the character was approaching his 400th birthday. How do gnomes celebrate their quadricentennial? They die. They turn into trees and die, leaving their trusty forest friends to roam the world cold and alone. No wonder Nick Jr. reran this heartwarming tale for 20 years straight.