The story is set in "the future, just a little after the present day…. To respond to disasters beyond human comprehension and the increasing complexity of crime and mishaps, the mobile emergency police Hyper Rescue (an organization newly formed by the government primarily for life-saving) developed 'Drive Heads' that are specialized with police, fire-fighting, and rescue capabilities.
Drive Heads' are special vehicles that change from car forms to humanoid walker vehicles. The grade schooler Gou Kurumada and other children found to be suitable become drivers and join forces with the mobile emergency police and other adults. Even now, they race to the scene to protect the peace and security of all humanity. Go Rescue!
Summary taken from: MyAnimeList