Rachel tries to launch a comeback into the McKinley High social stratosphere with a little help from Brittany. Meanwhile, Sam starts a tribute band.

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.