Spider-Man: 017b - Magic Malice

At the Castle Theater (first mentioned & saved from demolition in "Farewell Performance" Spider-Man TV (1967), Blackwell the Magician is performing to a packed house. One of the attendees is the Green Goblin, watching him from the catwalk. He realizes that if he could learn Blackwell's tricks, he would be able to embark upon a unprecedented crime spree. He leaves the theater to ransack Blackwell's house while he's otherwise occupied.