Daniel Craig: Will doesn't think there's anything really that wrong at first. Just life happening.
Rachel Weisz: You know, it's a beautiful little house with a garden. It's a dream house, until it's not.
Daniel Craig: And things sort of get stranger and stranger from there.
Rachel Weisz: it gets just very paranoid and intense and it feels like the house is haunted.
He has to go out there and figure it out for himself.
Near the beginning of the movie you find out that bizarre twist. There's this big secret, but then the question is wether that's reliable. There are different layers of truths and untruths. And it's a puzzle really.
He's been living in a fantasy world, because it looks like he killed his wife and his children. And there it sort of starts to crumble.
It's questioning the whole nature of reality and the secret about Will's identity. It slowly unravels. Everyone else is sure he's done something terribly wrong.
Somehow he's gotta figure it out.