Chris Hemsworth told Esquire which ?Avengers: Infinity War? co-star is the worst at keeping secrets. Mark Ruffalo. Yet Hemsworth also said that Ruffalo is ?the person I probably love the most.? He said Ruffalo?s kind personality allows him to forgive any time Ruffalo gives away a plot point. Ruffalo is known for famously revealing at D23 Expo that half of the characters in the film die.