Instant Reveal the top four cards of your library. You may put a creature card from among them into play. It has "At the end of your turn, return this creature to its owner's hand." Then put the rest of the cards revealed this way on the bottom of your library in any order.1
If you reveal more than one creature card, you can only choose one of them to be put into play. [Dissension FAQ 2006/04/13]
If the creature leaves play before the end of turn, it won't return to your hand. [Dissension FAQ 2006/04/13]
If you put a creature into play this way during your end-of-turn step, it won't be returned to your hand until the end of your next turn. [Dissension FAQ 2006/04/13]
If a creature (such as Clone) copies the creature, the copy will not have the "At end of turn" ability. [Dissension FAQ 2006/04/13]