My Longest Day is a humor-filled documentary of one young man's struggle with his father's cancer diagnosis. Matthew Steinhart traverses his family history and the scientific aspects of cancer and surgery, all the while relating his father's plight to popular culture and contemporary humor. Despite the seriousness of cancer, this documentary remains light by poking fun at today's taboos and cultural idiosyncrasies. However, it never forgets the severity and complications that cancer possesses, declaring the necessities of family and friendship in times of need.