'Glee' gears up to end the season, as well as the seniors' time at McKinley High, in the 'Props' and 'Nationals' episodes, airing back to back this Tuesday (May 15) at  8PM ET on FOX.

In the two-episode event, the New Directions are preparing for the Nationals and determined to win.

In 'Props,' fans will also finally be treated to the body-swapping episode they've been promised all season long. Tina suffers a head injury, so the entire episode takes place within her mind when she's seeing stars.

Rachel even tells Finn, “We have to win it. There’s really no other alternative.” Considering that the New Directions sing 'We Are the Champions' within the 'Nationals' episode, we're guessing -- but don't know for sure -- that they do just that.

'Nationals' also features Lindsay Lohan guest-starring as herself, which will be a treat to anyone who follows gossip rags -- it'll be fun to see the oft-troubled starlet poke some fun at her own life while listening to the cast's covers of Queen, Lady Gaga, Nicki Minaj and more.

'Props' Episode Song List:
Puck + Coach Beiste, 'Mean' (Taylor Swift)
Glee Cast, 'I Won't Give Up' (Jason Mraz)
Glee Cast, 'Because You Loved Me' (Celine Dion)
Rachel + Tina, 'Flashdance / What a Feeling' (Irene Cara)

'Nationals' Episode Song List:
Trouble Tones, 'Edge of Glory' (Lady Gaga)
Rachel, 'It's All Coming Back to Me Now' (Celine Dion)
New Directions, 'Paradise By the Dashboard Light' (Meatloaf)
Vocal Adrenaline, 'Starships' (Nicki Minaj)
Vocal Adrenaline, 'Pinball Wizard' (The Who)
New Directions, 'Tongue Tied' (Grouplove)
New Directions, 'We Are The Champions' (Queen)

Watch the ‘Glee’ Promo for ‘Props’ and ‘Nationals’