"Double Jeopardy: Part 1", known as "Disqualified from the WDC!? Heartland's Assassins, Droite and Gauche" in the Japanese version, is the thirty-seventh episode of the Yu-Gi-Oh! ZEXAL anime. It first aired in Japan on December 26, 2011 and in the United States on November 10, 2012.
On the second day of the WDC, Flip falls down from a tree and wakes himself up, after he separated with Yuma and the others. He was hiding in a tree in order to analyze the other duelists but fell asleep. He decides to collect Heart Pieces but realizes that it's the second day and only strong people remain, and if he loses he'd lose his only Heart Piece. He then thinks of an idea. Elsewhere, as Yuma is talking to Tori and fits his 4th Heart Piece into its container, he then notices that Astral isn't around him, and he's in the ship within the Emperor's Key wondering what he is. Elsewhere Flip is collecting Heart Pieces using his "tricky ideas" and even takes Spencer's Heart Piece and in return he can choose any number of pieces he wants from Flip's bag.
Spencer ends up getting disqualified from the WDC because the Heart Pieces Flip gave him were fake (they were candy). Flip then goes to see Nistro to qualify into the next round, and Nistro tells him to lick his Heart Pieces. Flip licks it, says it's candy and tell Nistro he was tricked, but Nistro doesn't believe him and ties him up with rope. Then Yuma and Tori arrive and Dextra recognizes Yuma as "the noisy little boy". Nistro reveals that as punishment for fabricating Heart Pieces his Deck will be confiscated, he will be disqualified from the WDC and he would be deprived of all future participation in the WDC for the rest of his life. Nistro also says he will make sure he never duels again by beating him out of Heartland City.
Knowing this, Yuma decides to Duel against him but instead Dextra agrees for a 2-on-1 match. If Yuma wins, Dextra and Nistro will forget what Flip did and leave him alone, but if Yuma loses he takes Flip's punishment, which Yuma accepts. Meanwhile, Astral is still in The Emperor's Key, and notices Yuma is starting a duel. He goes to help him but is stopped by Number 96 who has broke free with the help of the other "Numbers" (excluding "Utopia"). Astral asks why are the other "Numbers" helping him, and Number 96 says that all "Numbers" want destruction.
The Duel begins, and Astral is still inside the Key so Yuma couldn't use the Numbers. Number 96 asks Astral to remember his mission, and to come to their side. He is then attacked by him, but Number 39: Utopia appears and protects Astral, and Number 96 then asks Utopia if he is standing against them. He then summons his true form, "Number 96: Dark Mist", and says that he'll absorb him. Back at the Duel, Dextra has destroyed both Yuma's monsters and he is now down to 2400 LP. It is now Nistro's turn, and he attacks Yuma directly with "Hammer Bounzer". Luckily, Yuma's got a plan. He Special Summons "Gagaga Gardna" in Attack Position and uses its effect and discards a card but he's still hit with damage. Yuma is now at 1000 LP, and Nistro then uses "Blade Bounzer" to attack "Gagaga Gardna". Yuma then discards a card but still takes damage, and as Nistro uses the effect of "Blade Bounzer" to discard a card to attack again, Yuma discards the last card in his hand to protect his monster but is still hit with damage. Nistro then uses the effect of "Blade Bounzer" again but Yuma has no cards in his hand, and he's nearly out of monsters on his field and LP.
Turn 5: Dextra
Dextra Normal Summons "Swallowtail Butterspy" (1800/1200). Dextra activates the effect of "Butterflyoke", changing "Tasuke Knight" to Attack Position. This activates the effect of "Morpho", decreasing the ATK and DEF of "Tasuke Knight" by 1000 each (1700/100 → 700/0). "Morpho" attacks and destroys "Tasuke Knight (Yuma 4000 → 3500). As another monster inflicted Battle Damage, Dextra activates the effect of "Swallowtail", decreasing the ATK of "Rai Rider" by the amount of damage that was inflicted (1200 → 700). "Swallowtail" attacks and destroys "Rai Rider" (Yuma 3500 → 2400). As "Rai Rider" battled, its effect activates, meaning that "Swallowtail" may not attack next turn. Dextra Sets a card.
Turn 6: Nistro
Nistro Normal Summons "Blade Bounzer" (1800/1200). "Hammer Bounzer" attacks Yuma directly, with its effect activating as Nistro controls no Spell/Trap Cards. Yuma may not activate any of his own during this battle. Yuma activates the effect of the "Gagaga Gardna" in his hand as a direct attack was declared, Special Summoning it (1500/2000) in Attack Position. A replay occurs and "Hammer Bounzer" attacks "Gagaga Gardna", but Yuma activates the other effect of "Gagaga Gardna", discarding "Overlay Eater" to prevent its destruction by battle (Yuma 2400 → 1600). "Blade Bounzer" attacks "Gagaga Gardna", but Yuma activates the effect of "Gagaga Gardna", discarding a card in his hand to prevent its destruction by battle (Yuma 1600 → 1300). Nistro activates the effect of "Blade Bounzer", discarding "Copy Knight" to allow it to attack again. "Blade Bounzer" attacks "Gagaga Gardna", but Yuma activates the effect of "Gagaga Gardna", discarding the last card in his hand to prevent its destruction by battle (Yuma 1300 → 1000). Nistro activates the effect of "Blade Bounzer", discarding a card to allow it to attack again.