Watch Gwyneth Paltrow Get 'Happy' in New 'Glee' Song for 100th Episode

Glee reaches a pretty significant milestone on Tuesday — the premiere of its 100th episode. And in celebration of that fact, there are a heaping helping of former Lima friends heading back to their harried halls. Like Kristin Chenoweth... and Gwyneth Paltrow singing "Happy" . In fact, the actress also known as substitute teacher Holly Holiday, has a song all her own to sing during the 2 hour long celebration of jazz hands, after-school specials, and oft-uncomfortable and/or nonsensical orchestrations of popular songs. The tune is Pharrell Williams' Academy Award-nominated hit from Despicable Me 2 (and also his latest, really good album, G I R L ), "Happy." And you can listen to the whole thing below!

With Mr. Schue (Matthew Morrison) tackling back-up vocals (alongside the Glee clubbers, because of course), the cover is pretty much a note-for-note reproduction of Williams' original, with Paltrow's brassy tone lilting about. The song is just one of several tunes on the upcoming album — because this show is literally nothing without its iTunes sales — celebrating the series' 100-episode run thus far.

1 Keep Holding On* -featuring Mark Salling (Puck)2 Valerie* -featuring Naya Rivera (Santana) and Heather Morris (Brittany)3 Defying Gravity*-featuring Lea Michele (Rachel), Chris Colfer (Kurt) and Amber Riley (Mercedes)4 Raise Your Glass* -featuring Matthew Morrison (Will) and Kristin Chenoweth (April)5 Toxic*-featuring Naya Rivera (Santana), Heather Morris (Brittany) and Dianna Agron (Quinn)6 Happy -featuring Gwyneth Paltrow (Holly), Kristin Chenoweth (April), Matthew Morrison (Will), Darren Criss (Blaine) and Amber Riley (Mercedes)7 Party All the Time -featuring Gwyneth Paltrow (Holly)8 Total Eclipse of the Heart*-featuring Matthew Morrison (Will) and Kristin Chenoweth (April)9 Loser Like Me*-featuring Darren Criss (Blaine), Kevin McHale (Artie), Chord Overstreet (Sam) and Jenna Ushkowitz (Tina)10 Be Okay -featuring Lea Michele (Rachel) and Naya Rivera (Santana)11 I Am Changing -featuring Amber Riley (Mercedes) and Chris Colfer (Kurt)12 Just Give Me a Reason -featuring Dianna Agron (Quinn) and Mark Salling (Puck)13 Don't Stop Believin'* -featuring Lea Michele (Rachel), Darren Criss (Blaine), Chris Colfer (Kurt), Matthew Morrison (Will), Kevin McHale (Artie) and Jenna Ushkowitz (Tina)