Yuki Sanada, a shy young man who struggles with social interactions due to frequent relocations with his grandmother, experiences a transformative encounter in Enoshima. Here, he meets Haru, an eccentric self-proclaimed alien armed with a mysterious water gun and fishbowl companion. Against Yuki's reservations, Haru befriends him and pulls Natsuki Usami, a classmate and fisherman, into their whirlwind of escapades. Join this unlikely trio as they embark on extraordinary adventures in Tsuritama!