Wonder-ful

Mercedes Jones (Amber Riley), who is recording her first album, returns to Lima with Mike Chang (Harry Shum, Jr.) and Kurt Hummel (Chris Colfer) to help coach New Directions for Regionals.

She helps Marley Rose (Melissa Benoist) improve her voice, and the two sing "Superstition" alongside Blaine Anderson (Darren Criss) in the auditorium.

Kurt learns his father Burt Hummel's (Mike O'Malley) cancer is in remission, and celebrates his recovery with a performance of "You Are the Sunshine of My Life".

In New York, Cassandra July (Kate Hudson) finds out about Rachel's callback and initially seems to continue on her harassment of her, setting up an extremely difficult dance exam for the next day and telling her she'll go to her audition to see her fail.

Mercedes becomes disappointed when the record label tries to force her to change her image to have the album released, and decides to cancel their contract and pursue her dreams through different means.

[4] Kevin McHale, who plays Artie, had proposed Sagal—along with Harry Connick, Jr.—as the character's yet-to-be-seen parents at the Glee panel held during the 2012 Comic-Con shortly before the fourth season began shooting.

Other recurring characters in this episode include Kurt's father Burt Hummel (O'Malley), Burt's wife and Finn's mother Carole Hudson-Hummel (Rosemont), glee club members Wade "Unique" Adams (Alex Newell), Marley Rose (Benoist), Jake Puckerman (Artist), Kitty Wilde (Tobin) and Ryder Lynn (Blake Jenner), and two unnamed sycophantic students at NYADA (Patrick Stafford and J.D.

Katey Sagal appears as Artie's mother, Nancy Abrams