Here’s a bit of “Wonder-ful” news, Glee is about to dedicate an entire episode to the music of Stevie Wonder! Here’s the not-so-awesome part. Season 4, Episode 21: "Wonder-ful" is the second to last episode of the entire season.

Curious about what to expect in Glee’s “Wonder-ful” new tribute episode? Look no further than right here.

- Glee Promo: 4x21 — In-Depth Analysis of a Stevie Wonder “Wonder-ful”

We've scanned the promo, looking for clues about what's to come. Here's what we've managed to uncover so far. 

- Glee Spoiler: First Look Kate Hudson’s Return — Trouble for Rachel! 

Cassie (Kate Hudson) is baaaack! Rachel better watch herself.

- Cory Monteith Rehab: Missing Glee's Season 4 Finale?

 

Sadly, there will be no more Finn on Glee this year. Actor Cory Monteith will be absent from both this episode and the next week’s season finale, as he focuses on overcoming a substance addiction in rehab.

- Cory Monteith Rehab: Glee Has to Rewrite the Season 4 Finale Scripts

 

However things end up going down, that’s not necessarily the way they were going to be originally!

- Kurt’s Back in Ohio, and He’s Hanging Out With Blaine

 

Does this mean they’re about to get back together? We certainly hope so! (In fact, we’re hearing that some very big things are in store for Klaine in the Glee Season 4 finale.)

- Artie and Kitty Pay a Visit to His Mom

 

What’s more, Mrs. Abrams is played by none other than Sons of Anarchy actress Katey Sagal. We can’t wait to meet her!

 

Credit: Glee on Fox on YouTube Photo: First Look at Glee 4x21: “Wonder-ful” — Meet [Spoiler]'s Mom! (VIDEO)

Music

Glee Music Spoilers! First Listen + Song List: Episode 21: “Wonder-ful” — Leaked 

- “Superstition,” performed by Blaine (Darren Criss), Mercedes, and Marley (Melissa Benoist)

- “You Are the Sunshine of My Life,” performed by Kurt (Chris Colfer)

- “Uptight (Everything’s Alright),” performed by Cassie (Kate Hudson)

- “Signed, Sealed, Delivered I’m Yours,” performed by Kitty (Becca Tobin)

- “Higher Ground,” performed by Mercedes

- “For Once In My Life,” performed by Artie (Kevin McHale)

- “I Wish,” performed by Jake (Jacob Artist) and Marley