Hypocrisy targets Heroes, not cards placed on them. Therefore if you have 8 cards in hand, then I can target 8 Heroes to return to your hand. The player of Hypocrisy would get to control the order in which Heroes are returned to hand (much like the player who plays a "mass band" card gets to choose which special abilities activate in which order). However, if a Hero has placed enhancements and not enough "room" for them, then I believe the player with control of the Hero would get to select which enhancements also follow and which are "dropped."
