A spy, an assassin, and a mind-reader get together to form a family. Hilarity ensues. Spy x Family has a unique high concept premise that could only come from a mashup of family genre tropes mashed together to create something new. It's the type of high concept that desperate Hollywood screenwriters would give their fifth vertebrae for. It's also the type of high concept mashup that, somehow, only could have come out of Japan.
Codename: Twilight is a master spy, the best of the best. Efficient, pragmatic, cool under pressure, he is at the top of his game. The mission is all, and he follows orders to get things done. Then he gets an order that stumps him: to have a cover family in order to keep tabs on a man who's a threat to the fragile peace between East and West. Twilight, the lone wolf, hates the idea but diligently sets out to find the perfect people who can pose as his wife and kid. He adopts a little girl named Anya straight from an orphanage and picks a shy, socially awkward woman named Yor for his wife. What he doesn't know is Yor is an assassin on a mission of revenge, and Anya is a telepath whose psychic powers were unearthed by secret experiments. Yor doesn't know Twilight is a spy, and precocious Anya is the only one who knows all their secrets. Anya is the only one who knows her "parents'" secret, but she plays along just to see how this all pans out, and she doesn't want to be sent back to the orphanage. Without realizing it, these three dysfunctional people become a real family-of-choice even as they keep hiding their true natures from each other.
Farce is hard to do in comics, but creator Tatsuya Endo pulls it off with deft comic timing and deadpan flair. Twilight has to improvise ways to hide his real identity when bad guys come gunning for him in front of Yor and Anya. Yor has to keep making up increasingly nutty lies to cover up her reflexes and fighting skills. Any just goes along for the ride, reading their minds through everything. The balancing act of a fake family lying to each other and the absurd comedy gives the series its unique flavour. It's as if Endo took on the story as a dare and has to keep up the juggling act for as long as possible. The first volume of any manga series is always the most fun. The story and characters are at their freshest and most surprising when they're being established, and Spy x Family makes the journey look like a fun one.