Now that we know a musical episode is in the works over on the Grey's soundstages, let's see how previous shows have fared with similar stunts.

Buffy the Vampire Slayer - "Once More With Feeling"
Grade: A
Joss Whedon and Company outdid themselves with this Season 6 episode, which, in our books, not only ranks as the best musical episode produced, but also one of the best hours of television ever produced.  The four months that this one episode spent in production (and that the cast spent in training) were totally worth it. The premise is that a demon causes all the residents of Sunnydale to sing and dance their hearts out, often revealing their deepest secrets in the process. With a smart plot, a variety of musical styles, and some meta winks at the audience to top it all off, this episode is musical gold.

Scrubs - "My Musical"
Grade: A-
Perhaps the series was past its prime by the time this episode aired, but who cares. Simply put, without this episode, the world would never have been exposed to "Guy Love" and "Everything Comes Down to Poo."  Comedy + music = a satisfied audience.

Fringe - "Brown Betty"
Grade: B
This musical episode of this sci-fi series had the added benefit of being noir in style. And the premise was actually solid: Walter tells Olivia's daughter a fairytale of sorts while being hopped up on various recreational drugs. Points for Broyles' piano jazz and for how good Olivia looked in a trench coat and fedora; but we wish other characters, like Astrid and the Observer, could have belted out more tunes.

Ally McBeal - "Ally McBeal: The Musical, Almost"
Grade: D
"Almost", indeed. Major points off for pointless musical numbers and haphazard appearances from characters who have nothing else to do than to sing. But this episode has two saving graces: the vocal talents of both Jane Krakowski (as seen on 30 Rock) and guest star Randy Newman.

7th Heaven - Red Socks
Grade: F
It's not a good sign when a show decides to pull the trigger on a musical episode in its ninth season. And this episode feels like a Hail Mary that never had a chance. Pair thin singing chops with half-hearted attempts at dancing, throw in some mediocre plotlines and throwaway dialogue and you get a mess that is as far from heavenly as musical episodes get.

MORE ON THE MUSICAL:
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