Surrounded in complete darkness, Black looks up and sees Landorus, Thundurus and Tornadus towering over him. The three genies combine their powers, and unleash an energy blast towards him. Black cries out in horror as the ground is shattered beneath him, and begins to tumble downwards out of control.

At that moment, Black snaps his eyes open, and realizes that it was just a dream. He pants to catch his breath, and wipes a sweat off his cheek, relieved that he wasn't actually chased by the genies. Musha clamps its mouth on the boy's head, and tries its best to eat up the nightmare that he has been having, while Tula works to tighten the sleeping net that it has built for its trainer with its silk. Black believes that his possible ineligibility to take part in the League has left him shocked and unsettled, which gave him nightmares and made him dream of the three legendary Pokemon of Unova, the cyclone Pokemon Tornadus, bolt strike Pokemon Thundurus, and abundance Pokemon Landorus.

His mind drifts off to his president, White, whom he has actually not contacted since they parted ways, and wonders how she is doing now. Just as Black is having the thought, White, who is still back on the Battle Subway, takes a sneeze and startles her Deerling, Jessica. Ingo hopes she hasn't caught a cold from the chilly weather in the recent few days, and Emmet is more concerned whether she is going to pass it to them. White laughs that someone probably just talked about her, and the two Subway Bosses don't know how to respond to that. They then tell White to continue with her training before they reach their destination, and believe that it will further help develop her battling skills. Ingo remarks that she has certainly become a worthy component of theirs, and Emmet cheers that they should try to have a double battle.

Back on Black's side, he hesitates as he presses White's number of the Xtransceiver, but eventually decides to forget it. He believes that the girl must be working hard on the Battle Subway, and thinks he will simply worry her if he tells her about what happened. Nevertheless, in order to convince Drayden to let him take part in the League with only 7 Badges, he will need to obtain a Pokemon of remarkable strength. He recalls having actually encountered one of the legendary Pokemon Brycen mentioned, and flips out his Pokedex to check on it.

Just then, someone peeks over his shoulder at his Pokedex, asking what the Pokemon is, and Black replies that it is called Virizion. The person further questions where he saw it, and Black responds that the creature normally resides at the Rumination Field of the Pinwheel Forest. In that instant, he realizes that he has company, and bolts up to his feet. He turns around to see that it is Iris, and demands to know how she appeared. Iris is annoyed that Black sounded as if she is some kind of wild Pokemon, and says he should be grateful that she came looking for him out of her concern of his safety after he dashed off from the Icirrus Gym in the thick snow.

Black isn't really interested to mingle with the girl further, and excuses himself, muttering how fussy and pesky she is. Iris fumes that his attitude is really infuriating, and grunts that she will not share with him the great information which she brought with her in that case. The girl makes a face at him, and turns to leave with Fraxure, and naturally, Black is intrigued by her words, and starts going after Iris instead. He wants to know if she really has some great information to share, but the girl plays hard to get, and Black has to butter up and apologize for his impoliteness to get her to talk.

Iris leads him to the east side of the Route 6, and tells him that across the river is a place called the Mistralton Cave where a legendary Pokemon is said to reside. Black is curious as to where Iris got the information, and Iris states that she heard it from a weird man. As soon as she says that, she feels that she has worded that poorly, and corrects herself that it is actually a brilliant professor who told her, but when she turns around, she discovers that Black has already dashed off.

A while later, Black makes it across the river, and sees the dark entrance to the Mistralton Cave. Although he has chosen to believe Iris, he wonders if there is really a legendary Pokemon inside. At that moment, he hears someone shouting, and looks over to see that a finely dressed woman is yelling at a girl who wears a ponytail at the back of her head. Apparently, the woman is crossed that the girl is having hesitation, and hollers that it is absurd to turn back now that they have come so far. The woman sends out a Heatmor, and says she shall go in alone if the girl is reluctant to. With that, she steps into the dark opening of the Mistralton Cave, while the girl calls after her with a worried tone.

Black walks up to the girl to ask what is going on, and his sudden appearance startles the girl. Black apologizes for intruding, and after introducing himself, explains that he has overheard their conversation. The girl introduces herself as Shoko, and says people usually call her Shoko of the Patrat Show. Black puts on a confused look as he has never heard of the Patrat Show, and Shoko decides to show him. She sends out four Patrats from their Pokeballs, and gives one of them a Big Mushroom. She then takes out a music player to play a tune, and the four Patrats begin dancing and switching positions repeatedly with one other. When the music stops, the Patrats all strike the same pose, and Shoko wants Black to point out which Patrat is holding the Big Mushroom. Unfortunately, Black is made extremely dizzy by the act, and is having trouble talking right now, which causes to Shoko worry.

Soon, Black gets better, and Shoko explains that if someone manage to answer correctly, she will give off the Big Mushroom as a reward. Normally, she plays this act on the Marvelous Bridge, but she has been dragged here by the princess today. Black bolts at the word 'princess', and realizes that she is talking about the woman who just went into the Mistralton Cave. He wants to know if she is really the princess of some country, but Shoko reveals that it is actually just a nickname. She states that the woman is born from a wealthy capitalist family, whose social status makes her behave like a princess, but the two of them are also friends, which is she was asked to come along.

At that moment, a terrifying scream is heard from inside the cave, and Black exclaims that it is the voice of the princess. Shoko puts on a frightened and worried look, and says she has already warned the princess not to go in. Black believes that such a scream means the woman has encountered something really bad, and offers to help Shoko rescue her friend.

The two hurry into the darkness of the Mistralton Cave, and after navigating through winding pathways, arrive at its innermost part where they see two mighty four-legged creatures towering over them on a small cliff. Black recognizes the green antelope-like one as Virizion, and Shoko states that the brown bull-like one is its legendary companion, Terrakion. Black can see that Iris is telling the truth after all, and Shoko points out that there should be a third one, the one who is the normal resident of this Guidance Chamber.

Black believes that their top priority is to rescue the princess first, and sends out his Emboar, Bo. He thinks that it will be a good thing if he could capture these two legendary Pokemon and make them his companions, and orders Bo to use Flamethrower. However, to his shock, Virizion swings its head forward, and creates an aerial slash to cut through the flames. It then leaps off the cliff to charge towards them, and Black warns Bo to stay cautious as Virizion's horns are sharp like blades, which could cut through things around it like razor, and its agility is top-class among all Pokemon.

The green antelope unleashes a swirl of leaves as it approaches, and although Bo manages to pull Black out of the way, some of the leaves still sliced at the boy's trousers, cutting into his skin. Black winces that it is Magical Leaf, and rationalizes that Virizion must be a grass type, which means Bo's fire attacks have an advantage. With that, Bo envelops its two fists in flames, and starts chasing after Virizion with physical punches. Virizion adeptly hops from wall to wall inside cave, but Bo eventually manages to catch up with it. Just as the Emboar is about to land a punch, something cuts in to take the hit, and Black gasps that Terrakion has shielded itself in front of Virizion.

The boy grunts that the two Pokemon are working in perfect combination, and watches as Virizion retreats to the back, picking up the princess who has temporarily passed out. Terrakion then kicks back against the floor, and propels itself forward for a charge. Bo narrowly jumps out of the way, which causes Terrakion to ram into the cave's side wall, breaking a big hole right through it. Black exclaims at the brown bull's strength, and Shoko states that Terrakion has the top-class power charges among all Pokemon. Black is astonished that Shoko knows so much about the legendary Pokemon, and the girl explains that she has looked up on their information in detail since the princess wanted to capture them.

At that moment, the woman regains consciousness, and begins to flail around when she realizes that Virizion has held her captive. The green antelope hurls her down to the ground, and in the next instant, both Shoko and Black gasp that Virizion and Terrakion are about to attack her simultaneously with a Leaf Blade and Stone Edge. Fortunately, before the attacks land, Bo leaps forward and shields the woman from the blasts, taking the hits itself. Black thanks Bo for the sacrificial act, and Shoko hurriedly checks on the woman. She cries that she already said it was a ridiculous idea trying to capture legendary Pokemon, and doesn't understand why one must abandon their comfortable life and come looking for danger. However, the woman tells her to shut up, and states that the reason is adventure and romance.

She points out that as a member of the wealthy Riches family, she could always get what she wanted ,but adventure and romance are things that could not be bought or bargained. She believes that she could only discover true worth when she could create a path with her own strength to find what she is looking for. Shoko argues that there are many ways to create one's own path, and the woman barks that a cowardly and flustered girl like her will not understand the value of adventure of romance. She challenges what fun there is to perform the Patrat Show day after day on the Marvelous Bridge, and states that one must get out of their comfort zone to see the wide big world outside.

Shoko says she isn't afraid to be looked down on, but is certainly afraid of the horrible things out there. The woman is upset that Shoko still doesn't understand, and says they will not be young forever. She declares that she is sick of living a stable and uneventful life, and is determined to stand up and achieve something remarkable. She gets her Heatmor ready, and announces that she, Trish of the Riches, will show the world how she lives out both adventure and romance.

Meanwhile, on Route 6, Iris continues on her journey with Fraxure, and suddenly hears her name called. She turns around to see that it is the brilliant professor again, and the man, who is Cedric Juniper, the father of Professor Aria Juniper, grins that she should start remembering people's proper names. Iris states that she has told her friend Black about the Mistralton Cave, and Cedric is surprised to hear that Black is a friend of hers. He wants to know where he is now, and Iris replies that the boy has gone off to the cave because he wanted to battle the legendary Pokemon inside.

Cedric is slightly worried to hear that, and Iris wonder why. The man explains that apart from being powerful legendary Pokemon, Virizion, Terrakion ad Cobalion do not trust humans at all, and will definitely not hold back during a battle. Iris is curious to as why they have no trust in humans, and Cedric states that long ago, the three fought against humans in a great war.

Back inside the Mistralton Cave, Trish lights up two fire torches with the flames of her Heatmor, and states that her strategy is to target Virizion first, who is extremely quick but weak to fire attacks. She believes that it will be wise to break up the opponents and avoid them from collaborating with each other, especially before the third Pokemon appears, and puts on a determined look.

Standing on a ledge behind her, another four-legged creature watches in silence, and keeps its hostile gaze on the humans…