When free-spirited substitute teacher Holly Holliday fills in for the absent sex-education teacher, she joins forces with Mr. Schuester to teach the kids of New Directions the facts of life. Meanwhile, Emma heads up the Celibacy Club, and she and Dr. Carl address some issues in their personal life.

Proving that birds of a feather flock together, when another under-the-radar club at McKinley High needs helps raising funds, the glee club signs up to help. But when Sue hears about the show of support, she moves quickly to put the kibosh on it. Meanwhile, relationships are tested and big decisions will be made.