Once Upon A Time season 6 episode 16
Episode title: Mother's Little Helper
Gold and Belle convince Emma to help Gideon, explaining that together they can stop the Black Fairy. Henry experiences a disorienting shift in his powers that forces Regina to seek counsel from the previous Author. Meanwhile, in Fairy Tale Land, Hook attempts to win the assistance of an old adversary by betting his most prized possession on a game of cards. And, in a flashback, the Black Fairy tortures young Gideon in hopes of molding him into the perfect apprentice.
