Christian Bowman

The joy at Claire's safe return is short-lived when Ethan pounces on Charlie, threatening to kill off the survivors one by one unless she's returned to him. The camp set up an alarm system and sentry duty to protect her, but when Boone takes his turn to guard, he dozes off and is awoken by Claire's screams.

The castaways' spirits are temporarily raised with the discovery of a transceiver in the wreckage; the group discovers handcuffs, a gun and an animal that shouldn't be able to survive in a tropical climate.

The Company wants Whistler out of Sona, and they want him out now. The escape plan explodes into action, but it's not Whistler who will be leaving the prison walls.

Locke helps Charlie begin a painful journey of withdrawal from drugs, and Jack is buried alive after a cave collapses.

It's crunch time for Michael and Linc as they prepare to hand Whistler over to Susan. Meanwhile, T-Bag's scheming at Sona finally pays off.

Michael, Whistler, McGrady and Mahone make their break from Sona. But Mahone seems like the odd man out along the way.