John Krasinski and Natalie Portman on teaming up to play sibling adventurers in Guy Ritchie's action-adventure, Fountain of Youth.

"Guy talked about that all the time and said, 'What if the fountain of youth was inside you? What if it's just a metaphor for the light inside you that you can either make brighter or dimmer? And what if you worked really hard to pull out all the things that made you joyful,