The game Wonder Dog follows the story of a young boy named Johnny, who is transported to a magical world through a dimensional portal created by a talking dog named Wonder Dog. In this new world, Johnny discovers that the evil Queen Vorka has taken control of the kingdom of Screamania and has imprisoned the prince and princess. Wonder Dog informs Johnny that he is the only one who can save the kingdom and rescue the royal family. To do so, Johnny must journey through various themed levels and defeat Queen Vorka's minions, as well as facing off against bosses in each level. To aid him on his quest, Wonder Dog grants Johnny the ability to transform into different forms with special abilities, such as a flying car, a submarine, a robot with extendable arms, and more. Johnny can also collect items to increase his health and time. As Johnny progresses through the levels, he faces various challenges and dangers, such as enemies, obstacles, and traps. However, with the help of Wonder Dog and his abilities, Johnny manages to overcome each obstacle and finally reaches Queen Vorka's castle. In the castle, Johnny battles Queen Vorka in an epic final showdown, defeating her and freeing the prince and princess from captivity. Johnny is hailed as the hero of Screamania and returns to his world with Wonder Dog, having completed his adventure in the magical world.