The movie really belongs to Mortensen, who allows Ben to be exasperating, arrogant and impatient but also warm, loving and caring. He’s a tough but adoring father, a grieving widower and an angry defender of his wife’s final wishes, and Mortensen plays all these notes and more with subtlety and grace.

Despite a frustrating fizzle of a finale, it’s a movie that enthralls the senses and engages the mind for two hours, proving no movie is too long when you’re having fun.

Captain Fantastic isn’t only one of the year’s best movies, but one of the best cast and best acted, right down to the smaller roles.

Though the film struggles to wrap up the proceedings in an overlong final act, it thankfully stays true to its characters by not oversimplifying a complicated subject.

Ross doesn’t run from the resulting sentimentality the way so many other directors do; nor does he undercut it with irony or sarcasm as has become the regrettable tendency in independent cinema.