A Night in the Nacrene City Museum! (Japanese: シッポウシティー！博物館で大冒険！！ Nacrene City! Museum Adventure!!) is the 14th episode of Pokémon: Black & White.
After arriving in Nacrene City and discovering that the Nacrene Gym is inside the city museum, our heroes meet a very scared man. His name is Hawes, and it turns out that he’s soon to become co-curator of the museum. He claims to have seen ghost-like apparitions recently, just as the museum is about to launch what is called the Secret Artifact Exhibition. The gang listens to the details of what has been happening, and Iris decides that an “angry spirit” is putting a curse on the museum. Cilan disagrees — he says that there must be a scientific explanation for everything.
The heroes came to Nacrene City and admire the colorful houses. Cilan explains those were warehouses, which were designed as houses by artists and admired by many. Ash came for a Gym Battle. Cilan tells the Gym is located inside the museum, so the heroes head there. However, the museum is closed, so Ash knocks on the door. Iris reads an exhibition is shown today, but Cilan does not see the reason why it should be closed. Suddenly, the heroes hear a scream inside the museum. A man gets hunted by a rock, so he breaks out of the museum. He points at the Dome Fossil that chased him, but the heroes see nothing.
The heroes head inside and see Dome Fossil standing on a pillar. The man explains the heroes what happened. After the workers placed the artifacts for the new exhibition, the man went to check the artifacts. Suddenly, lights started flickering and he heard someone coming. A ball of flame appeared, so the man rushed out of the museum and called the workers back. Even if nothing was determined, the man decided to postpone the exhibition and checked the artifacts once more, but got chased by the Dome Fossil. Ash admits that is a weird situation. Iris claims the museum got cursed by an angry spirit and something must be done, scaring Axew. Cilan thinks she is overreacting, thinking there is a scientific explanation to all this.
Ash wants a Gym Battle, but Iris replies they haven't got the time for that. The man, whose name is Hawes, the curator, explains Lenora, the Gym Leader and his wife, is not present at the moment. Hawes gives them a tour of the museum, showing the Dome Fossil, a proof shell Pokémon lived more than 3,000,000 years ago. He also shows them the biggest skeleton model of a Dragonite. Hawes shows them a meteorite, which came from outer space, containing cosmic energy. They enter a room, where they see suits of armor and a replica of Cofagrigus' coffin. Iris has a feeling this has got to do with the curse, but Cilan replies she has no evidence, which is but a hunch. Ash sees a mask, so Hawes explains it belongs to a Yamask. Iris senses something about the mask. Finally, Hawes shows the library, where one can read about the artifacts.
Ash admits he is hungry. Iris yells at him, but Ash tells it was a joke. Cilan asks Hawes if they can sleep here, bearing in mind they can look after paranormal activities. Hawes sees the kids are courage, but Iris tells Ash is the only kid around, annoying him. Before going to sleep, Ash checks the egg. Hawes asks what happens if the things start getting dangerous, though the heroes know they will be ready for such actions. At an alley, Team Rocket gets approached by Pierce, who tells them their next mission: to switch the real meteorite in the museum with the fake one. He also tells them the real meteorite is and is not their real target, confusing them. At the museum, Iris wakes Ash and Cilan, as she feels a strange chill, though Cilan dismisses it to be another hunch.
Suddenly, a fog appears, scaring Hawes. Iris believes the spirits will attack, but Cilan tells the air conditioning is broken. Some footsteps are heard, as an armor appears before the heroes. Iris asks Cilan how does he explain that. Cilan claims objects move, but release low-frequency sounds. The armor draws the blade, so Cilan thinks the armor is controlled by strings. Pikachu uses Quick Attack, hitting the armor, which reforms back. Pikachu uses Volt Tackle, knocking out the armor, which reveals a ball of fire. Cilan tells it is an electrical discharge rather than a ghost. Ash sends Oshawott, who uses Water Gun to douse the flame. The helmet hovers and chases Hawes, but Cilan tells it is the magnetic field that causes such effect. Pikachu uses Iron Tail, knocking out the helmet.
Iris thinks the spirits chase Hawes, but Hawes does not see what he could've done something wrong. Suddenly, it rains inside the museum, so Cilan tells the sprinklers are broken. The rain stops and a cry is heard. Iris thinks it is a sad spirit, but Cilan believes something is squeaking. They go further in the museum and see the mask crying, though Cilan explains it is condensation. The mask tries to get out. Iris tells the spirit is inside the mask, but Cilan tells it is just attracted like a magnet. The skeleton Dragonite appears, so Cilan starts doubting himself. The skeleton attacks the glass, so Cilan sends Pansage, who uses Bullet Seed, knocking the skeleton, which causes a cry. Hawes unlocks the display, which causes the mask to be attached to Cilan, possessing him, who fires balls of fire.
Iris tells he is taken over by the spirits, as Cilan did not believe in spirits. Iris tries to reason with the spirit, who tells it is lotten away. Suddenly, Lenora appears, who asks Hawes where did he get the mask. Hawes remembers that the mask was laying on the ground, so thinks it was like a thank-you gift. The skeleton Dragonite is formed, so Lenora sends Watchog, releasing light. Lenora asks Yamask to come out, so the mask comes out of Cilan's face, forming Yamask. Lenora thinks Yamask was sleeping and the mask got knocked out of its reach. When it woke up, it thought the mask was stolen. The heroes see it used a variety of moves. Iris tells she was right, but Cilan doubts that. Hawes and Lenora apologize to Yamask, who forgives them. Ash sees it is a cool Pokémon.
The Yamask leaves, while the sunrise is seen. Ash thinks this is a good time for a Gym Battle, so Lenora is pleased for another challenger.
- The Moveset the Yamask used in this episode is as follows:
- Psychic to move the armor and skeleton of a Dragonite.
- Haze to create a fog.
- Rain Dance to cause indoor rain.
- Will-O-Wisp for a spooky flame.
- The title of the episode is a parody to the movie "Night at the Museum".
- Professor Oak's Live Caster: Axew
- The "Who's That Pokémon?" is Yamask.