TOO MUCH INFORMATION TO POST FOR EVERYTHING. :( So I'll just post what episode 5 to 8 are, which cast members are returning and songs. okay.
4x05 - The Role You Were Born to Play
So in conclusion for the songs.
Hopelessly Devoted To You from Grease. Sung by Blaine
Juke Box Hero by Foreigner. Sung by Ryder and Finn
Blow Me (One Last Kiss) by P!nk. Sung by Unique and Marley
Born to Hand Jive from Grease. Sung by Mercedes, Marley, Jake and Ryder.
Everybody Talks by Neon Trees. Sung by Kitty and Jake.
4x06 - Glease
Songs; (All from Grease!)
You're The One That I Want. Sung by Marley, Ryder, Santana, Rachel, Finn, Mercedes and Mike.
Beauty School Dropout. Sung by Blaine
Look At Me, I'm Sandra Dee. Sung by Kitty with Unique, Brittany, Tina and Sugar.
Look At Me, I'm Sandra Dee (Reprise). Sung by Marley.
There Are Worse Things I Could Do. Sung by Cassandra, Santana and Unique.
Greased Lightning. Sung by Sam and Ryder with Joe, Mike and Jake.
4x07 - Dynamic Duets
Holding Out For a Hero by Bonnie Tyler. Sung by Marley and Kitty
Heroes by David Bowie. Sung by Blaine and Sam
Dark Side by Kelly Clarkson. Sung by Blaine with The Warblers.
Superman by REM. Sung by Jake and Ryder.
Some Nights by fun. Sung by Tina, Sam, Marley, Kitty, Ryder, Jake, Joe and Blaine with New Directions
4x08 - TBA
Live While We're Young by One Direction. Sung by Sebastian and Hunter with The Warblers
Whistle by Florida. Sung by Hunter with The Warblers
Home / Homeward Bound by Simon and Garfunkel/Phillip Phillips. Sung by Quinn, Finn, Puck, Mercedes, Mike and Santana
Lets Have a Kiki / Turkey Lurkey Time by/from Scissor Sisters/Promises, Promises. Sung by Kurt, Rachel and Isabelle.
Come See About Me by The Supremes. Sung by Quinn, Santana and Brittany
*Gangnam Style by PSY. Sung by Tina with Kitty, Ryder and New Directions.
Skyfall by Adele. Sung by Blaine and Marley with New Directions
* = Tina will lead the song as Jenna is the only person able to sing/speak Korean. It sounds amazing so far! (There's a preview on Youtube)
4x09 - TBA
Songs (so far)
Somethin' Stupid by Frank Sinatra and Nancy Sinatra. Sung by Sam and Brittany
4x10 - TBA [Christmas Episode!]