The plot is set partly in a near future in which artificial intelligence is in control of everyone's lives and human emotions are perceived as a threat.
A brilliant boy discovers that he can manipulate time using a family heirloom. He soon team up his siblings in returning to the time of their parents' separation from their in hopes of changing the outcome.
Follows troubled youth Chan Lok-kwun as he accidentally enters the Walled City, discovers the order amidst its chaos, and learns important life lessons along the way.