A master spy must maintain his cover as the head of a fake family while preventing a terrorist attack involving trained dogs. Twilight, codenamed "Loid Forger," is tasked with forming a family to get close to a target. His new family consists of Anya, a telepathic adopted daughter, and Yor, a deadly assassin posing as his wife. In this volume, the Forgers consider adopting a dog, a decision complicated by Loid's need to thwart a plot by terrorists who plan to use attack dogs against a foreign minister. Loid must use his espionage skills to neutralize the threat while keeping his family's true natures hidden.

Spy x Family, Vol. 4 continues the series' trend of blending high-stakes espionage with heartwarming, comedic family dynamics. The narrative skillfully balances Loid's professional mission to stop a terrorist plot involving attack dogs with the Forger family's domestic pursuit of a new pet. Readers often praise the series for its unique premise and the charming interactions between the main characters, particularly Anya's endearing reactions to the unfolding events. This volume further develops the intricate web of secrets and the found-family aspect that has garnered a significant following.