What have I done today to make me feel proud? Why, voted, of course! I love to vote, and only wish I could do it more often. I take plenty of online surveys, but it doesn't have quite the zing of actual democracy in action.

We begin the episode with a flashback to last week's elimination, when Adam was voted out. Sami congratulates the remaining contestants, and informs them that they're halfway through the season. Already! And by "already" I mean, "Oh God there are seven weeks still left?" This next week is going to be an all-out war, Sami says, and then calls in some real live Marines! They are Sergeant Gonzales and Sergeant Corona. They have no weapons, except for those guns on their arms. Frado is a former Marine, and so is excited about this development. One of the Marines shout-talks at the contestants, in that military way. He says that they'll be living like U.S. Marines for the next week. They'll be staying at Camp Pendleton -- the largest training facility on the west coast. And they'll be walking, talking, and acting like U.S. Marines. Most importantly, they'll train, work and sweat like U.S. Marines. And Marines are no slouches. The other sergeant says, "You think Bob and Jillian are tough? You ain't seen nothing." Cut to some very concerned looks from our contestants.

Sergeants Corona and Gonzales rush the contestants out, get them outfitted in Marine helmets and vests, and put them in a terrifying giant vehicle. Several hours later, they arrive at Camp Pendleton. The contestants are introduced to their combat instructors, which include Gonzales and Corona. They have three minutes to get into their new gear. Staff Sergeant Giaretta tells us that the contestants are in for some hard work, just like regular Marines. While the Marines are training to go into combat zones, the Biggest Losers are training to save their own lives. Frado tells us that he's a veteran of the Gulf War. He's told his wife in the past that if he went back to boot camp he'd never get to this weight again, and thinks this is all meant to be. Aaron's brother is a military vet. He always wanted to follow in his brother's footsteps but couldn't because of his weight, so this is a bit of a dream come true for him. Mark is also excited to be exposed to military discipline, which he needs in his life. We'll see if he changes his tune after a few hours.