Ryan has a New Years Eve surprise for semi-girl-friend Taylor, a trip to Las Vegas, while she went for sexy lingerie. Spoiled, moody Summer rages at 'immature' Seth for having made no particular festive plans; after encouragement from dad, who has urgent court business himself, his plan B is to beg eternal last resort Ryan to take them along, promising to pay for the best room Cohen money can buy. During the trip, Taylor begins to wonder whether Summer may be pregnant from her recent trysts with Seth, while he discovers the home pregnancy test in Taylor's purse and jumps to the wrong conclusion, while panicking Taylor pretends to Ryan she's the mother-to-be. Things take another turn for the worse when Summer's purse is stolen and the four of them end up at a rave populated by people dresse