Ready for Big Brother?

The 15th cycle of CBS' summer staple is upon us, with the premiere right around the corner. With 16 houseguests ranging in age from 22 to 37 and several new twists, the summer may be more chaotic than ever.

In preparation for the Big Brother premiere, two previews from the Wednesday opener have been released — and they show a major contrast in houseguests' reactions.

PHOTOS: 'Big Brother 15': Meet the 16 Houseguests

The first clip (above) features the first group of houseguests — Andy Herren, Candice Stewart, GinaMarie Zimmerman and Judd Daugherty — to enter the house.

To say they're enthusiastic is an understatement. Andy, a self-proclaimed "superfan," can't contain his excitement, while the majority of them set up shop in one of the bedrooms. The editors are already eyeing certain story lines, with Judd talking about GinaMarie's beauty in the Diary Room.

PHOTOS: 'Big Brother 15': First Look at the Brand-New House

The second clip (below) follows surfer dude David Girton, part of the last group of houseguests to enter the house, when he discovers from Jeremy McGuire that the bed situation isn't looking good for him. How does he react to the news?

Big Brother premieres 8 p.m. Wednesday on CBS.

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