Episode 620

"A Critical Situation! Punk Hazard Explodes" is the 620th episode of the One Piece anime.

Short Summary
Monet was moments away from activating the self destruct button when she felt her heart being stabbed and collapsed. At the same time, Caesar Clown is shown stabbing the heart, believing it to be Smoker's. The Straw Hat Pirates and their allies are still racing towards the exit of the collapsing lab when they feel the explosion of the SAD room and then see Shinokuni on their trail. Smoker, seeing that they nearly reached safety, questions Trafalgar D. Water Law about how he possessed his heart the whole time. Trafalgar Law reveals the clever deception he played on the mad scientist, when he returned the heart of Monet to Caesar without Caesar being the wiser.

At the tanker, Baby 5's missile attack failed to take down Franky Shogun and their duel begins anew. Buffalo contacts Doflamingo to explain the situation. After confirming that the island wasn't destroyed as intended, Doflamingo decides to tend to the matter himself and is seen somehow flying over the sea towards Punk Hazard.

Long Summary
After Baby 5's attack, Franky Shogun is seen lying on the deck surrounded by flames. Baby 5 reforms through her ability after her Missile Girl attack. Buffalo asks if she needs some weapons he picked up, although comments how she is already a weapon herself. Baby 5 says that they are blessed but the weapons were bought because she felt "needed", due to her personality. Franky Shogun punches her from behind but she jumps out of the way and transforms into a revolver. Frank takes the full blast but laughs it off, condescendingly saying that it would not work.

On the tanker, Caesar realizes that Baby 5 and Buffalo are there to save him while still holding Smoker's heart.

In the SAD production room, Vergo is seen talking to Doflamingo through a Den Den Mushi, where the latter apologizes to the vice admiral for what is to come. He tells Vergo that he was his longest companion and thanks him for his hard work and devotion. Even in pieces, Vergo smiles.

In the SAD transport corridor, Momonosuke is still in shock and in grief over his father's state. Brook mistakes him for an eel. The group then hears an explosion, which Law says came from the SAD production room. Rocks begin to fall down from the ceiling. Law tells them that the corridor is a tunnel built into the mountain and if it were to collapse, all the occupants would be buried alive. Coincidentally, the way in front of them is blocked. However, Zoro simply clears the path with ease.

Monet is still in building C, ready to set off the deadly gas explosion with the button. A series of frames shows scenes such as the children crying, Sanji kicking away a rock and Doflamingo sitting in his room at Dressrosa. Monet says goodbye in her mind to the Shichibukai, saying that he will be the next Pirate King.

Caesar then prepares to kill Smoker, using a sharp object to pierce his heart. He laughs and says "Die, Smoker!" However, Smoker is shown to be perfectly fine while Monet collapses with blood flowing out of her mouth. She pulls up her top to reveal a cube-shaped hole in her chest. Doflamingo realizes something is wrong and orders her to answer him, but Monet collapses and dies from being stabbed in the heart by Caesar.

On the cart, the children urge it to move forward. Smoker asks Law why Caesar thought he had Smoker's heart. Law has a flashback to the moment when Caesar outlines the bonds of their contract - Law must give his heart and Caesar would give Monet's heart to him. After fighting Smoker, Law had two hearts in his hands, Smoker's and Monet's. Unknown to Caesar, Law had returned Monet's heart. He explains this to Smoker, saying that Caesar simply misunderstood and Law "kindly gave back the heart of the secretary, Monet". He underlines this action with his belief that those who do good will get good things in return. Law then calmly asks if anyone can produce wind as there would be gas in the air when they exit. The Marines are surprised, claiming that no one has such an ability. However, Nami tells them that she can, leaving the Marines even more surprised. Someone else shouts that the exit is coming up.

On Dressrosa, a young girl is seen looking for Doflamingo. She asks an old man about his whereabouts, who replies that he should be on the fourth floor. The girl says that he was not, and the window was wide open. The old man seems calm but dark as he is states that he has no idea and that he went alone again.

Somewhere over the sea, Doflamingo is running in midair. He is talking to Baby 5 and Buffalo, who are telling him that they are having a problem with a metal guard. Doflamingo seems uninterested, telling them to finish it off and noting that there was no big explosion. Doflamingo then states that he is coming to Punk Hazard.

Anime Notes

 * When Caesar stabs Monet's heart, the hole on Monet's chest wasn't shown in the anime.
 * In the anime, Caesar stabs Monet's heart at the same time the SAD room explodes. In the manga, the SAD room explodes before Caesar stabs her heart.
 * The anime shows that Law gives Smoker back his heart after finding the rail car while the manga did not show exactly when Law returned the heart.
 * The anime adds the following:
 * After Zoro cuts a large piece of rubble blocking the passage, everyone in the rail car cheers for him.
 * The deadly gas chases after the rail car.