I think Jack felt so helpless in the other's camp that Juliette was the only other who also felt like she couldn't escape, and that made him trust her. He is so sweet, and tries to look for the best in everybody, but it may come back to bite him.

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" I push this button every 108 minutes, I don't get out much."

"Theres a time for living low down, theres a time for getting high. A time for peace, a time for fire. A time to live, a time to die."

The real art of conversation is not only to say the right thing at the right time, but also to leave unsaid the wrong thing at the tempting moment.