Meet Otis Milburn (Asa Butterfield) -- a socially awkward high school virgin who lives with his mother, a sex therapist. Surrounded by manuals, videos and tediously open conversations about sex, Otis is a reluctant expert on the subject. When his home life is revealed at school, Otis realizes that he can use his specialist knowledge to gain status. He teams up with Maeve, a whip-smart bad-girl, and together they set up an underground sex therapy clinic to deal with their fellow students’ weird and wonderful problems. Through his analysis of teenage sexuality, Otis realises he may need some therapy of his own.