The story tells the story of Qin Lie, a top agent code-named "Head Wolf", who was ordered to protect the 5-year-old daughter Lin Xiao (code-named "Little Apple") left by a deceased top scientist during a mission. He originally thought it was just an ordinary protection task, but gradually discovered that Little Apple is no ordinary child - she has the amazing ability to perceive and influence high-dimensional "information fields", and is the "key" that the mysterious forces of all parties compete for. Qin Lie had to transform from a cold "knife" to a "super dad" who juggles rocking cars, broccoli and Pikachu badges. In the neighborhood relationship full of smile traps and the undercurrent of invisible information warfare, he used a steely will and a heart that has become extremely soft to protect this cute high-dimensional baby who can open the "door of return", fight against the mysterious organization called "Deep Well", and pursue the ultimate truth behind her missing parents.
