The series is set in the near future, when an automobile company named JHC Motors is depicted to have created the Watch Cars, which are miniature sentient robotic cars that are supposed to have become good companions to children and adults alike. Watch Cars are depicted to have become a global trend. There is a Battle League where Watch Cars and their trainers battle. Jino, one of the young Watch Car Masters, goes to the Watch Car Battle League with his Watch Car Blue-will, but The Rangers of Darkness an evil force to takeover al the watch cars in The city, Jino and his friends must stop them.