Prisoners ending explained

What happens

Loki finds Anna alive at Holly Jones's house and rushes her to hospital, while Holly leaves Keller trapped in a pit. Taking children was her way of making others lose their faith, a motive that recasts everything before.

The last image

Loki, standing outside, hears the faint sound of Keller's whistle from beneath the ground, and the film cuts to black.

Two readings

1 · Keller is rescuedLoki heard the whistle, so he will dig Keller out and Keller will live.

2 · We never knowThe cut leaves his fate open, and what you imagine reflects you more than the film.

What it says

The film ends before the answer because its question is moral, not procedural. Keller's certainty put him in that pit. By withholding rescue or punishment, it won't let you settle whether his desperation was righteous or cruel.