Hector (Simon Pegg) is a quirky psychiatrist who has become increasingly tired of his humdrum life. As he tells his girlfriend, Clara (Rosamund Pike), he feels like a fraud: he hasn't really tasted life, and yet he's offering advice to patients who are just not getting any happier. So Hector decides to break out of his deluded and routine driven life. Armed with buckets of courage and child-like curiosity, he embarks on a global quest in hopes of uncovering the elusive secret formula for true happiness. And so begins a larger than life adventure with riotously funny results.