John gets sick from radiation poisoning, but Ann invites him into the house and slowly they begin to trust one another, even becoming somewhat domestic. She may not survive another winter, but a nearby poisoned waterfall may be their saviour. By building a hydroelectric waterwheel they could generate power for the farm, but it would also mean tearing down a local chapel and using the wood. Despite the clear transubstantiation metaphor, this doesn't sit well with Ann, who still clings to her Christian faith in the face of all this suffering – her family left to look for survivors and never returned.
Just as the sexual tension between the two seems to have reached its breaking point, there enters a third party. The mysterious and charismatic Caleb (Chris Pine) has found his way to 'paradise', but it is hard to tell at first if he is a threat. In contrast to John he shares Ann's faith – or is he simply saying so. Is he genuinely a nice guy, or is he scheming to bump John out of the way to win Ann. Maybe John realises Caleb is a better match for Ann, or maybe John is about to recognise he truly loves her – the rational scientist confronted with emotional irrationality.
These small psychological moves are the meat of the second half of Craig Zobel's (Compliance) loose adaptation of Robert C O'Brien's popular young adult novel. There is certainly a lot of bare symbolism and unspoken feelings, but not a lot of action. No comment about race is made until far into the film, and its mention also doubles as one of the films sole jokes. But what begins as a deeply philosophical survivors' story soon deflates into a contrived love triangle – two Adams vying for the attention of one Eve. If John and Caleb are intended as twin pillars of science and spirituality, in the end they seem like two basically decent people who realise that there is no solution to this equation that involves both of them. Who ends up with whom in the end? It scarcely seems to matter. Yet the depth of the world and all three of the performances are just enough to stay through from A to Z.