The Avengers director and cast sat down with Entertainment Weekly to talk about the film, discussing which character feels the most alone.
"Hawkeye, it's got to be Hawkeye," Robert Downey Jr said.
"I couldn't tell you," Jeremy Renner responded of his character.
"See, the problem is buried so deep," Downey Jr joked, before continuing: "His origin story is horrible. It's nothing but trauma."
"Everyone has their own baggage and that's why I think it was an uphill battle to try and marry all the conflict of all these individual characters," Chris Evans, who plays Captain America, added.
"We are all isolated; we are all dealing with our own problems and these... characters all have these problems," Whedon explained.
"The beauty of the thing is when they realise that not only does that not matter in the bigger scheme, but the way to work those problems out is to subsume themselves to something that matters more," he said.
The Avengers opened to a record-breaking $200.3m at the US box office during its opening weekend.