GLEE “Duets” Season 2 Episode 4 October 11, 2010 Glee, News Watch a sneak peek and check out a first look of the upcoming episode of GLEE “Duets” Season 2 Episode 4 which airs Tuesday October 12 at 8pm on FOX. You can read all our coverage of Glee here. Episode Synopsis: GLEE “Duets” Season 2 Episode 4 – The glee club works on a duet assignment, and Finn and Rachel plan to throw the competition so that Sam can have a shot at winning. Meanwhile, a love triangle between Mike, Tina and Artie develops in the all-new “Duets” episode of GLEE airing Tuesday, Oct. 12 (8:00-9:01 PM ET/PT) on FOX. Cast: Matthew Morrison as Will Schuester; Jessalyn Gilsig as Terri Schuester; Jane Lynch as Sue Sylvester; Lea Michele as Rachel Berry; Cory Monteith as Finn Hudson; Jayma Mays as Emma Pillsbury; Dianna Agron as Quinn; Chris Colfer as Kurt; Kevin McHale as Artie; Amber Riley as Mercedes; Mark Salling as Puck; Jenna Ushkowitz as Tina; Naya Rivera as Santana Lopez; Heather Morris as Brittany; Mike O’Malley as Burt Hummel Guest Cast: Harry Shum as Mike Chang; Iqbal Theba as Principal Figgins; Josh Sussman as Jacob Ben Israel; Dot Marie Jones as Coach Shannon Beiste; Chord Overstreet as Sam Evans; Romy Rosemont as Carole Hudson Also watch any Glee episodes that you may have missed here.