'Barking mad' is the only possible way of describing the main character, Allie, who takes his family into the forests of South America to escape the madness and corruption that, in his view, has made the US unlivable.
The return to origin par excellence.
The disappointing note is the rest of his family. Although crazy, extreme in his beliefs, at least Allie is real, while the rest of his family may well have been extra luggage. Not until the very end do they start to rebel to his madness, when it is too late.