Modern special agent couple Zhou Qingqing and Xiao Chen cross through time due to an explosion during a mission. Zhou Qingqing becomes the substitute bride for the Xiao family, but the Xiao family faces a raid and exile due to Xiao Chen's treason charge, and Xiao Chen's whereabouts are unknown. Relying on her space system and agent skills, she protects the old and young of the Xiao family on exile while secretly investigating her husband's grievance. Along the way, she meets Xiao Chen, who is using the pseudonym of an account assistant to secretly investigate the case. Without knowing each other's true identities, the two join forces to track down and expose Prince Xin, who intends to rebel. Prince Xin privately casts weapons, frames Xiao Chen, and creates confusion. The two work from the inside and outside to expose the conspiracy, clear their names, and the couple recognize each other to jointly eliminate evil.