Archeops In The Modern World! (Japanese: 化石復活！古代怪鳥アーケオス！！Fossil Revival! Ancient Mysterious Bird Archeos!!) is the 36th episode of the Best Wishes series, and the 693rd episode of the Pokémon anime. It first aired in Japan on June 16, 2011 and first aired in the United States on October 8, 2011.
Our heroes stop to visit their old friends Professor Juniper and Dr. Fennel on their way to Nimbasa City, just in time to witness an amazing event: Dr. Fennel uses a special Pokémon restoration machine to restore an Archen from a Plume Fossil!
The ancient Pokémon has some trouble adjusting to its modern environment, rejecting Cilan’s specially prepared food and complaining in an ear-splitting voice. Flying also proves difficult for Archen, even though it’s the ancestor of all Flying-type Pokémon. This gives our heroes and the researchers a monumental opportunity to witness the historic birth of Pokémon flight! At first Archen struggles to get off the ground, even with help from Ash’s Tranquill—but after it evolves into Archeops, it takes off easily!
Meanwhile, Dr. Fennel’s machine has drawn the attention of Team Rocket, who hack into it to steal the data. They also try to catch Archeops, but after losing a heated battle, they withdraw to celebrate their data-stealing success with Doctor Zager.
Worried about how Archeops will survive in the modern world, Dr. Fennel and Professor Juniper start making plans to create a proper environment for it...and then they discover the purpose of its persistent cries when three other Archeops appear! And so, united with others of its own kind, Archeops happily goes off with its new friends, and our heroes bid them a fond farewell.
Ash and his friends are in a building on the way to Nimbasa City, with Professor Juniper showing them a Plume Fossil and telling them that the ancient PokémonArchen came from this Fossil, immediately catching the interest of all but Iris. Ash recalls Nacrene City's Gym Leader Lenora and her fascination with Fossils as well. Professor Juniper slips slightly and tells her everyone has their own opinions. She shows Ash, Iris, and Cilan a picture of Archen, and Iris comments that if Archen is the "First Bird Pokémon" then it must be Tranquill's great-great relative.
The group continues to read the manual as Professor Juniper looks over at Fennel, who is on the computer. The Fossil is placed in a machine that is powered by Musharna's Dream Smoke. The machine is then activated, scanning the Fossil and then creating Archen. After the machine stops, they open up the machine and find Archen. A seed seems to fall off of Archen's plumage. Initially, Archen tries to fight off Ash and friends, confused and using Peck on everyone. Ash attempts to calm down the Archen but instead they run right into each other. Archen wears herself out and falls asleep. Professor Juniper brings out her camera and starts filming the Archen. Meanwhile in another location, Team Rocket is listening in on the action while planning how they are going to try and capture the Archen. Archen wakes up and starts crying, as the seeds that appeared when Archen was revived started growing and sprouting. Archen's cries shatter windows. Ash grabs Archen trying to calm her down, after of which she does. Ash attempts to feed Archen, but she spits it out and escapes through the broken window and into the trees outside. Archen spits out the tree's fruit as well.
Ash brings out Tranquill to help teach Archen to fly while Iris brings out Emolga to help but she uses Attract, which fails indicating that Archen is indeed a female. Instead of helping Archen, Emolga uses Volt Switch to force Stunfisk, and due to curiosity, Archen uses Peck on Stunfisk, causing it to become surprised and use Thunder Shock. Archen uses her cries again while the sprouting seeds start growing even more, turning into a tree. While learning to fly, Archen starts to fly for short distances. Archen cries out in happiness causing the growing tree to grow even larger breaking the machines, and going right out of the window. Archen climbs up the new tree to eat the new fruit, and ends up loving that fruit. Archen cries out in delight and evolves into Archeops. Archeops shows that she can fly to everyone, then all of a sudden, Team Rocket strikes. Team Rocket has Yamask use Night Shade and set the tree on fire while they try to get away. Ash brings out Roggenrola and Oshawott to put out the fire. Team Rocket uses an electric net to capture the Archeops, which enrages her, using Dragon Breath to break free and attack them.
After Team Rocket gets away, everyone looks at the tree which was now completely destroyed. Archeops begins crying out and a flock of Archeops hear her cries and come to her. Everyone says their goodbyes to her and the flock flies away. Dr. Zager informs Team Rocket that even though they failed to capture Archeops, they were able to obtain all of the data that was needed.