More Glee cast members have been announced to be coming back for the show's landmark 100th episode.

Dianna Agron, who starred as Quinn Fabray in Glee's first three seasons, will be coming back for episode 100, according to co-creator Ryan Murphy. This will be Agron's first appearance on the show since guest starring in season 4. Murphy announced the news of her return on Twitter this week.

Agron was one of the only cast members who could not appear on the Finn (Cory Monteith) memorial episode earlier in the season.

Additionally, frequent guest star Kristin Chenoweth - who plays April Rhodes - is also slated to return for the 100th episode.

Agron and Chenoweth join other returning cast members, including Amber Riley (who played Mercedes), Mark Salling (Puck), Harry Shum, Jr. (Mike) and Heather Morris (Brittany) who will be returning for the episode.

Glee Spoilers: Songs for 'Frenemies' Include Chris Colfer & Adam Lambert Duet? 

During the episode, which is set to air on Tuesday, Mar. 18, 2014 at 8 p.m. on Fox, the senior class at McKinley High will reminisce on their high school experience as graduation approaches. While reminiscing, the cast will be singing new versions of the iconic Glee songs.

Glee fans have chosen all of the songs that will be sung in the episode from a list of 30. Among classic songs that were included on the list were Don't Stop Believin' by Journey, Imagine by John Lennon and Keep Holding On by Avril Lavigne.

Glee will return for the second half of season 5 on Tuesday, Feb. 25 at 8 p.m. on Fox.

Watch the trailer for next episode of Glee here:

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