Castle (Nathan Fillion) and Beckett (Stana Katic) will learn just how dangerous the world of a cappella can be in the midseason premiere of ABC's Castle.

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ABC has released a new plot synopsis for the upcoming midseason premiere of Castle, which is titled "Tone Death."

"When a body is found in the theater of Martha's latest show, Castle and Beckett's investigation leads them into the unexpectedly dangerous world of competitive a cappella," the synopsis reads. "'High School Musical's Corbin Bleu guest stars."

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Other guest stars include Arnell Powell as Chris Jackson, Reilly Brooke Smith as Robyn King and Sonya Eddy as Olivia "Mama" Toussaint.

The midseason premiere features both Jon Huertas (who plays Esposito) and Susan Sullivan (Martha) singing, according to a new Entertainment Weekly report.

For fans who are still confused on the schedule for the second half of season 8, let's break it down. While early reports had Castle returning on Feb. 1 (or even earlier, in January), the network decided to push it back a week. It is now premiering on Feb. 8, and to make up for the lost week, ABC plans to air another new episode on Sunday, Feb. 14 followed by another new episode Monday, Feb. 15.

Check your DVR to make sure it's set to tape on this special night.

Castle returns for the second half of season 8 on Monday, Feb. 8 at 10 p.m. ET/PT on ABC.

Tags: Castle television ABC