Brace yourself for an emotional rollercoaster October 10, when Glee will air its memorial episode to the late Cory Monteith. During the "Farewell to Finn" tribute, the cast will reportedly sing such songs as "I'll Stand By You" and "Seasons of Love" from Rent. Ryan Murphy, Glee's co-creator, said of shooting the show that "it was very rough, and it was very rough with Lea... I think the performances are quite stunning." Watch a promo of what's in store below, with such heartbreaking images as the McKinley students turning Finn's locker into a shrine, a sobbing Lea Michele and tearful Chis Colfer. We're already teary ourselves about this upcoming tribute.