“Comeback” episode!

The episode, which is called “Comeback”, will air later this winter and also feature Rachel and Mercedes (Amber Riley) diva’ing it out on a tune from Rent. Ryan Murphy explained about 'Justin Bieber episode', “Those [tributes] are reserved for artists with big catalogs,” he explains. “Bieber comes up in episode 13 as a small plot point. Sam (Chord Overstreet) sings a JB song to win Quinn’s (Dianna Aragon) approval."

SPOILERS ALERT!

1.Sam will form a boy band and sing 3 Justin Bieber songs.

2.According to Brad Falchuk atleast one of Sam's performances will be sung to Quinn and the same song will impress the other guys to the point that they want to get involved.

3.During the above performance Sam will copy Justin Biebers hairstyle.

4.Rachel and Mercedes will sing a duet, the song being from the musical 'Rent'.

5.In the above scene Sue and Rachel will dance together.

6.Iqbal confirmed on twitter that he filmed a scene with Dianna and Cory (Quinn and Finn).

7.Jesse may return in either this or next episode. Jim Groff said that Jonathan Groff would be filming for Glee in January once his show in London finished. And the show finished on January 15.

8.Apparently Finn and Rachel won't get back together in this episode. 

SONGS

TBA from Rent. Sung by Rachel and Mercedes.

Baby by Justin Bieber - Sung by Sam and his boy band (to Quinn). 

TBA by My Chemical Romance - Sung by Sue and New Directions.