Black and White arrive on the island of Liberty Garden after boarding a ferry from Castelia City and staying on it for a whole day. A tired-looking White recalls that the owner of the massage shop gave her the pair of ferry tickets as thanks for allowing her BW Agency mascots Tep (now Nite) and Gigi to feature in the massage's latest advertisement. White also had to reiterate many times to the shop owner that Black was not her boyfriend. Black then remembers that Professor Juniper called him earlier and asked him to run an errand. Though Professor Juniper was initially in a bad mood when she called, she praised Black's progress, especially that of his Pokédex, and assigned him the task of investigating the Pokémon Victini at Liberty Garden, which can be reached by boarding a ferry from Castelia's Liberty Pier. Black then asks how he is supposed to board the ferry, and Professor Juniper replies that he needs a Liberty Pass. Thankfully, White overheard the conversation and remembers that the massage shop owner who gave her a pair of tickets was talking about Liberty Garden.
Upon White's request, Black explains what Victini is, according to his research. He concludes his explanation by yelling his pledge. White, almost deafened by the louder-than-usual yelling, is worried that her employee might startle other visitors, but suddenly realizes that she and Black are the only ones on the island. Black explains that Liberty Garden is a restricted area, and it took a lot of persuasion to convince the captain of the ferry to let them on the island. Black turns to look at the pier, which the captain thought was broken, and finds that it isn't damaged at all. Intrigued, Black has Musha clamp on his head, and starts his detective work. Black reveals to White that he noticed, even before his mind was blanked out, that the Liberty Garden's lighthouse has an extra floor on it. White compares the lighthouse to photos of it that Black had gathered earlier, and finds that he is right. Black then states that he saw a V-shaped pattern flash across the lighthouse, and wonders what it is. He is suspicious about the lighthouse, though, and orders Brav to use Aerial Ace on the extra floor.
The wall crumbles, and three Team Plasma Grunts are revealed to have been hiding inside the lighthouse. However, Black notices that they are keeping residents of the island hostage. The leading Grunt confirms this and says that her Gothitelle put everyone else on the island to sleep with Hypnosis. Vowing to eliminate Black for interfering, she orders the other two Grunts' Gothorita to attack Nite, Tula and Musha. She also orders her Gothitelle to "protect Victini", and Black gasps upon hearing that. The leading Grunt claims to have heard Black do his homework, and states that the V-shape that Black saw flashing across was in fact Victini, which the three Grunts have already liberated. According to the Grunt, Victini refused to let her protect it, and tried to flee from them. She gestures to Gothitelle, and a Victini materializes in midair. Victini appears to be in pain, and upon seeing that, Black immediately gets furious at the Grunts. He claims that they are hurting Victini because they themselves are hurt by Victini's refusal of their protection. With that, he orders Brav to attack Gothitelle, but Gothitelle simply slithers away. The leading Grunt states that Victini is reaching its limit after being chased for three whole days.
Once Victini does reach its limit, and starts to fall from the sky, the leading Grunt commands Gothitelle to knock it out with the slightest touch. Brav shields itself in front of Victini just as Gothitelle's attack is about to hit. The leading Grunt snickers at Black's hypocritical strategy, but suddenly Brav gains strength and manages to strike Gothitelle with an Aerial Ace. Black finds out through his Pokédex that Victini must have channeled its unlimited energy to Brav. Then, upon Black's command, Brav knocks Gothitelle out with Brave Bird. By this moment, Nite, Tula and Musha defeat the two Gothorita, and the residents being held hostage start to wake up. Knowing that their plan has been foiled, the three Team Plasma Grunts flee from the island, with the leading Grunt swearing her vengeance to Black. Meanwhile, Brav hovers towards Black with Victini on its back. After Black thanks Victini, it does a V sign with its hands while winking and then disappears.
Later, Black contacts Professor Juniper to inform her about his encounter with Victini. After Black finishes the call, White wonders why Black didn't catch Victini. Black states that he doubts whether Victini would open up if he himself wasn't strong in the first place, and believes that he and his team should get stronger first. Finally, Black and White get ready to leave the island by heading to the pier. In Professor Juniper's lab, Professor Juniper finishes reviewing the data of Victini that Black sent her, and is now sure that Black possesses the right skills for the job of completing the Pokédex. A voice comments that skilled trainers often encounter dangerous situations, and Juniper turns around to see that her father has paid a visit. Addressing Juniper by her first name Aurea, Cedric Juniper states that he has come to help his daughter fix the broken Pokédexes, and Aurea is pleased to hear that. Having overheard the conversation between Aurea and Black, Cedric voices his own concern of Team Plasma being at large, and Aurea agrees, knowing that it was the same organization that ambushed Bianca on the streets of Castelia. Cedric then takes out the Poké Ball of his Samurott, and muses that it's been a year since the incident happened.