We Know Where You're Going, Eevee! (Japanese: イーブイどこいくの？あのコに会いにどこまでも！Eievui, Where Are You Going? To Go Anywhere to Meet Up!) is the 99th episode of the Sun & Moon series, and the 1,038th episode of the Pokémon anime. It first aired in Japan on December 2, 2018 and in the United States on March 29, 2019.
A familiar Eevee has been making its way across the ocean toward Alola, and its journey has been filled with adventure. A series of harrowing encounters—including a brush with Team Skull—has tested its determination, but when it finally finds our heroes, it’s as happy as can be! After forming a bond with Popplio, Eevee’s ready to join Lana’s team…but not before Lana gives it a name: Sandy! Lana and her family are thrilled to get to know her new partner—and Sandy’s excited to get to know them, too!
A familiar Eevee scoffs down a Nanab Berry and afterwards smiles out of fulfillment. A series of scenes from the Where Are You Going, Eevee? segments detail Eevee's journey before it reached Melemele Island's shores. As it emerges from its tree hollow home, Eevee spots a Heart TrimFurfrou and tackles it to get its attention. However, Furfou is none too pleased and frowns at Eevee. As Eevee attempts to rush into it again, Furfrou dodges and Eevee lands face first in a pile of sand. The pair's brief encounter ends when Furfou's SurferTrainer calls for it to come home. Eevee is instantly reminded of Ash and his classmates' Pokémon and rushes to find them.
Elsewhere, Lana emerges from her room after being disturbed by Harper and Sarah's cheering. The twins happily announce that their father will be returning home. Lana's mother enters the room and confirms that her husband will indeed be coming home after catching all the Pokémon for a lab, and they'll celebrate his return with a family feast. Lana adds that she'll buy some malasadas for dessert, and her younger sisters are thrilled by the idea.
Lana, with Popplio in her arms, walks into the Hau'oli City Mall and catches Eevee's attention. While wondering through the center, Eevee also attracts the attention of Pershie as it waits for its Trainer who is busy trying on jewelry. The AlolanPersian waves Eevee over and appears friendly, but as Eevee gets closer Pershie takes a quick swipe at it. Eevee flees in fear, but Pershie pursues it. As Lana orders her malasadas, Popplio spots the familiar-looking Eevee and rushes off to rescue it from Pershie. Lana soon realizes she is by herself and abandons her order to look for Popplio.
Meanwhile in the fruit market, Ash and Anela watch as Ash's Pokémon enjoy some Berries. Pikachu soon spots Lana as she runs passed and alerts Ash. Ash quickly learns that Popplio is missing. Elsewhere, Popplio has managed to catch up to Eevee. The pair seek refuge from Pershie behind a bush, but the Persian soon spots Eevee's tail and pounces on them. Popplio and Eevee are forced to run, but Popplio is struggling to keep up its pace on land. In a last-ditch effort, Popplio latches onto Eevee’s sides and launches into an Aqua Jet to stay away from Pershie. The trail of water leads to Pershie slip up. Soon, Popplio is forced to make a sharp turn as the Furfrou from earlier in the day stands in the middle of the street. The evasive manoeuvre avoids a collision, but Eevee and Popplio go on to fall into a nearby canal. Pershie watches on from a footbridge but retreats after its Trainer calls it back.
Sophocles and Mallow join Ash and Lana to look for Popplio. Soon after Lillie spots her classmates from her car window and has her chauffeur stop the car to allow her out. Coincidently, Kiawe and his Charizard were flying overhead and soon land to offer their assistance. The pair fly off to begin an aerial search, and Rowlet eagerly flies in another direction.
Eevee and Popplio have washed up onto a beach. Eevee soon spots a Garbodor, Zubat and Salandit playing nearby and rushes over to them. Popplio quickly realizes the trio of Pokémon belong to Team Skull Grunts, Tupp, Zipp and Rapp. However it is too late, as Eevee tackles the trio of Pokémon and angers them. Popplio intervenes as Tupp and his cronies arrive on the scene. Rapp immediately spots Eevee and hugs it because it is cute. She demands that they bring it home, but Zipp is quick to remind Rapp that having an Eevee around would only irritate Tupp because of his history with Ilima. Tupp then considers the idea and thinks that having an Eevee by his side would actually attract girls to him, just like it did for Ilima. Tupp and Rapp begin fighting over Eevee and pulling its arms. Rowlet soon spots the seaside squabble and alerts Ash to the scene. Despite Popplio's Bubble Beam, it is Pikachu's Quick Attack that saves Eevee from the tug-of-war between Tupp and Rapp. Popplio catches Eevee before it hits the sand. Lana is overjoyed to see Popplio but is perplexed by Eevee, who also greets her. Rotom is thrilled to see a wild Eevee as it happily nudges and high-fives the group's Pokémon. Ash and his classmates quickly realize that the Eevee is seemingly friends with their Pokémon already.
Tupp demands Ash and his friends hand over the Eevee to them, but this immediately infuriates Rapp and the pair argue once again. Lana scoops the Eevee in her arms as the trio of Grunts continue to quarrel. Ash is unimpressed by Team Skull's behavior and shouts that they don't deserve Eevee because they do not treat Eevee properly. The claim immediately infuriates Tupp, Zipp and Rapp and the trio decide to take Eevee by force. Ash calls on Pikachu's assistance, but Popplio, wanting to defend its Eevee friend, decides to join the confrontation. The trio of Grunts make the first move, with Salandit launching a Flame Burst, Garbodor attempts a Sludge Bomb and Zubat screams out a Supersonic. Lana calls for Popplio to use Aqua Jet, but the attack instead develops into a powerful wall of water which washes over Team Skull's attacks. Everyone is surprised by the surge of power and Rotom confirms that Popplio has learned a new move, Surf. Lana is even more shocked to see Eevee join Popplio atop the wave and Eevee then sends Team Skull blasting off with its Double-Edge. Kiawe and Charizard are startled as the Grunts soar passed them, and the pair soon join Ash and the others. Eevee is left with a large bump on its head from the impact, but is happy to be with its friends. Lana pets both Popplio and Eevee, as the others note that the pair of Pokémon make a great team. Ash suggests that Lana that she should catch Eevee, and the idea startles Lana at first. She watches as Popplio and Eevee play in the ocean, and seeing its affinity with the sea she goes onto nicknames it "Sandy". Lana and Popplio formally ask Eevee to join them, and it happily agrees to the idea. With that, Lana pulls a Dive Ball from her pocket and throws it into the air. The Dive Ball soon catches Sandy, and after a few sways, the capture is complete. Lana performs a victory pose with the Dive Ball in hand.
Back at home, the family feast is all prepared as Harper and Sarah parade around with Sandy. Lana's father arrives home, and the twins happily embrace him. Sandy rushes into Lana's father to greet him, much to his surprise. Lana explains that she only caught Sandy today and that it loves the sea. Lana's father instantly remembers that he recently saw an Eevee out at sea riding on a Mantine. Lana goes on to give Sandy's long fringe a haircut. With the hair now out of its eyes, the family takes a photo to commemorate the occasion.