Music has always been an important part of Grey’s Anatomy. But in last night's episode, it played a much bigger role: The cast sang some of the songs that were previously heard on the show, such as “Chasing Cars” by Snow Patrol, “How to Save a Life” by The Fray, “The Story” by Brandi Carlile and “How We Operate” by Gomez.

Although Chandra Wilson admits she was “scared and in denial about the whole thing” as the episode’s shoot date approached, she was glad she got to participate. “We did it in a way that’s kind of cool, with the iconic songs from Grey’s that people know. I sang about four different songs. I think people will enjoy it,” says Wilson, who has been having fun with her character’s latest love interest, Nurse Eli (Daniel Sunjata). “Right when you think you know everything about Dr. Bailey, you see another side of her." A more playful side, perhaps? "She’s trying to tap into it,” Wilson says.

Entitled “Song Beneath the Song,” the episode picks up with Seattle Grace’s doctors in crisis following the car accident involving Callie (Sara Ramirez) and Arizona (Jessica Capshaw) that happened in the final moments of the March 24 show. Private Practice’s Addison Montgomery (Kate Walsh) made a return appearance in last night's episode, which was written by show creator Shonda Rhimes.

Grey’s Anatomy: The Music Event soundtrack was released yesterday.

(Photo: ABC)