Wayne Whittaker Jr. is a UFO-specialist, who's been pursuing alien activities in the last 30 years. He claims to have a great knowledge on aliens, but Sam thinks otherwise. He even insults Wayne telling him he "sucks at hunting UFO's".
Eventually, it is revealed that Wayne isn't in fact a human, but a Leprechaun, one of the Fairies, who's covering up the abductions committed by his kind by claiming it was the work of aliens. He was summoned to the town by an ignorant Mr. Brennan, who was unaware of the price he'd have to pay, and the fact that fairies always "come to stay." In this episode, the price was the first-born sons of the whole town, starting with Brennan's own. The Leprechaun later confronts Sam after Mr. Brennan attempts to undo the spell that summoned him, killing the contractor for trying to go back on their deal. He and Sam then engage in a fight, in which Wayne easily overpowers him. However, Sam manages to incapacitate him by spilling salt, forcing the fairy to count each grain. This gives Sam time to finish the undoing spell, which sends all the fairies back.
Much like a Crossroads demon, Wayne is able to make deals with humans so that they may fulfill their wishes. However, unlike the denizens of Hell, fairies do not desire souls. In this particular case, Wayne desired first-born sons, although the reason why is not made expressly clear.
He also seems to be very powerful, employing what he calls "real magic." He claims to be able to lift Sam's soul from the Cage, and scoffs when Sam mentions that not even angels could accomplish that. Iron objects cause great pain for him, but it is hardly enough to slow him down, as seen when he shrugs off a shotgun shot from Sam. Silver seems to have stronger effects, as touching Sam's silver knife caused him to suffer burn wounds. His greatest weakness however, is when salt or sugar is spilt, for if one is a fairy, no matter how powerful one is, they are compelled to count each grain. Sam used this to great effect on Wayne, who was unable to resist even as Sam was reciting a spell to banish him.