This film manages the difficult task of being both a dark comedy and a poignant story. The balance keeps the movie from being too glib and smug due to too much of the former, and too mawkish and sentimental due to too much of the latter. As a middle-aged man in the throes of crisis, transition, and depression, Paul Rudd brings depth and nuance to his character, and as a teen boy stuck in a self-imposed routine, Craig Roberts, through the unforgettable Trevor, completely destroys the trite manner in which the disabled are so commonly portrayed in movies and television. The result is a buddy road trip movie like no other, a comedy filled with dark humor and dry sarcasm, but also a story filled with deep meaning, with so much clearly at stake for these characters.
Just when you think The Fundamentals of Caring is on the verge of committing the all-too-common indie-movie sin of making the characters a little too hip, clever, and hyper-aware for their own good, the suffering the characters have endured for far too long comes through, and the audience realizes that the hilarious sarcastic humor isn't shoehorned in by the scriptwriter, but is instead the defense mechanisms of characters trying to keep it together during a difficult time. While this is clearly due in part to the director, Rob Burnett, credit also goes to Rudd, Roberts, and Selena Gomez, who plays a teen runaway capable of as much caustic humor as the other lead characters.