Justice League Unlimited This Little Piggy (2004–2006) Online
The centuries-old enchantress Circe transforms Wonder Woman into a pig as revenge against Diana's mother. Batman and Zatanna work together to return her to normal, while B'wana Beast attempts to find the "Wonder Pig" before she's butchered at a slaughterhouse. It contains the famous scene of Batman singing the jazz standard "Am I Blue?" to a nightclub audience.
| Episode cast overview: | |||
 | Kevin Conroy | - | Batman / Bruce Wayne / Crimson Avenger / Lee Travis (voice) |
 | Susan Eisenberg | - | Wonder Woman / Princess Diana (voice) |
 | Jennifer Hale | - | Zatanna Zatara (voice) |
 | Rachel York | - | Circe (voice) |
 | Jack Carter | - | Sid (voice) |
 | Peter Onorati | - | B'wana Beast / Mike Maxwell / Red Tornado (voice) |
 | Laraine Newman | - | Medusa / Themis (voice) |
 | Chad Einbinder | - | Attendant / Factory Worker (voice) |
According to the audio commentary for this episode, Joker was going to make an appearance. He was going to be working on a trap for Batman, then Batman would appear holding the pig/Diana, trying to calm it down. The Joker would've seen him talking to the pig, and given up on his plans because he couldn't top that situation. But they decided not to add the scene.
Like in the DC Comics, Zatanna casts spells by speaking backwards: kcab ot lamron (back to normal), lleps eb nekorb (spell be broken), anaiD, emoceb namuh (Diana, become human), esrup raeppa (purse appear), dnufer (refund), stcejbo kcatta ecriC (objects attack Circe), elbat eb egac (table be cage)
Writer Paul Dini, whose favorite character on the series was Zatanna, met his future wife, illusionist Misty Lee, while writing the story.
Originally, the plot involved Circe turning the main male Justice League members into animals, with Wonder Woman trying to track them all down while Zatanna pursued after Circe. The idea changed and evolved over time, because it was considered too serious for this type of story.
According to the DVD commentary, Medusa's appearance was based on actress Tallulah Bankhead, and if they hadn't already recorded her dialogue before animating it, the producers would have instructed voice actress Laraine Newman to play the character to match.
Circe sings "Lulu's Back In Town," a song written in 1935 by Harry Warren and Al Dubin.
As alluded to by Batman, Circe features in Homer's epic poem, 'The Odyssey,' in which she turns Odysseus' men into pigs. The "Sirens" she mention in her stage show are also characters from the same story.
The final act of this episode features an incredibly rare moment of Batman singing! The song is "Am I Blue?" which was written in 1929 by Harry Akst and Grant Clarke.