Due to the ceaseless attempts on his life, Arthur Louis Zetes has grown into a sharp-eyed misanthrope who trusts neither flattery nor loyalty. As a final measure, he commissions a fully autonomous robot maid, capable of guarding him without the deceit of human emotion. His butler, Roy, presents Marie to him as the perfect solution—petrifyingly expressionless and unnervingly efficient—with every impression calculated to pass for a flawless automaton.

However, Marie carries a secret that could shatter the arrangement in an instant. She is, in truth, a bona fide human, as this level of technology is still impossible to obtain; her discipline as a martial arts prodigy is what easily allows her to pass as a machine. Buried in debt and in desperate need of work, she accepts the unusual assignment and commits to maintaining the illusion.

Arthur despises falsehood above all else, and one misstep could send the household spiraling into chaos. But in his obliviousness, and in his maid's earnest attempts to serve him without spilling the truth, the two begin to have an awkward relationship that transcends metal and flesh.