In the late autumn of 1948, Chen Jiaying, an underground party undercover agent, was betrayed and shot by her comrades on the top floor of the Peace Hotel. She was reborn and returned to the day she checked in in 1947. The internal space of the activated pocket watch can store items but cannot live animals. It can only delay the decay of food in the initial stage. Through precognition, Lin Mo, a progressive student who was supposed to die, was saved and discovered that his true identity was an underground party liaison. When the two handed over information in the cheongsam secret bag, a spatial mutation was triggered - invisible writing would appear on the paper they touched.
