May 20 (UPI) -- John Krasinski and Natalie Portman were among the stars who attended the premiere of their movie Fountain of Youth on Monday. The pair portray Luke and Charlotte, estranged siblings who reunite on a quest to find the famed mythical waters that are said to benefit those who drink from them. "They must use their knowledge of history to follow clues on an epic adventure that will change their lives... and possibly lead to immortality," an official synopsis reads. The premiere took