HENRY IS CALLED UPON TO RESTORE THE BALANCE BETWEEN HEROES AND VILLAINS, ON OF ABC'S "ONCE UPON A TIME"

"Operation Mongoose, Part 1 and Part 2" - The Author proves to be a formidable wild card and forges an alliance with Gold. Emma, her parents, Hook and Regina scramble to stop them, but when Gold and the Author turn the tables on heroes and villains alike, the prospect of any happy outcome appears worlds away. Henry discovers he has big shoes to fill as he steps up to save his family before the story's final page is turned. It's a race to the finish, and everything culminates with a shocking twist that will leave the residents of Storybrooke reeling, in the captivating two-part season finale of "Once Upon a Time," SUNDAY, SEPTEMBER 20 (8:00-10:01 p.m., ET) on the ABC Television Network. (Rebroadcast. OAD: 5/10/15)

"Once Upon a Time" stars Ginnifer Goodwin as Snow White/Mary Margaret, Jennifer Morrison as Emma Swan, Lana Parrilla as the Evil Queen/Regina, Josh Dallas as Prince Charming/David Nolan, Emilie de Ravin as Belle, Colin O'Donoghue as Hook, Jared S. Gilmore as Henry, Michael Socha as Will Scarlet and Robert Carlyle as Rumplestiltskin/Mr. Gold.

"Operation Mongoose Part 1" was written by Edward Kitsis and Adam Horowitz, and directed by Romeo Tirone.

"Operation Mongoose Part 2" was written by Edward Kitsis and Adam Horowitz, and directed by Ralph Hemecker.

"Once Upon a Time" is broadcast in 720 Progressive (720P), ABC's selected HDTV format with a 5.1 channel surround sound. This program carries a TV-PG,L,V parental guideline.

For more information on "Once Upon a Time," visit ABC.com/Once