Gwyneth Paltrow picked up a supporting actress in a comedy Emmy for her role as McKinley substitute teacher Holly Holliday. Her cover of Cee Lo Green's "Forget You" ranks as one of the show's most-downloaded songs, with more than 720,000.
Kristin Chenoweth's April Rhodes has popped up in three episodes of the show, playing an endearing alcoholic with the eyes for her childhood friend, Will Schuester. The boozy blonde eventually gifted McKinley with an auditorium when Sue Sylvester forced the glee club from its rehearsal space. Chenoweth, however, told THR that she thinks her "Glee days are over."
John Stamos' Dr. Carl Howell appeared in four episodes of the dramedy as a love interest for Emma -- and the denitist that gave Brittany and Santana laughing gas, paving the way for the duo's Britany Spears experience.
Jonathan Groff's Jesse St. James has recurred in a number of episodes, playing Rachel's boyfriend, a rival glee club performer-turned-New Directions member. Glee co-creator Ryan Murphy said in October that Groff would reprise his role as the coach of New Directions rival Vocal Adrenaline in Season 3.
Idina Menzel plays Rachel's biological mother and the adoptive mother to Puck and Quinn's daughter, Beth. The former Vocal Adrenaline coach left the group to be closer to both Rachel and give Puck and Quinn the opportunity to get to know their daughter, arriving at McKinley and ultimately starting up the school's second glee club, the Trouble Tones.
Carol Burnett played Sue Sylvester's absent mother, the frequently referenced Nazi hunter Doris Sylvester. She joined Jane Lynch for a cover of "Ohio" from the musical Wonderful Town in the Season 2 "Furt" episode.