The Secret Door in the Master Bedroom

From the back cover

Ryan lands at two in the morning to an alert from his smart mattress: dual-occupancy weight detected in his bed. Neither he nor his wife, Chloe, is home, and the housekeeper, Martha, is away with her family. Chloe insists by phone that her project keeps her away until the next night, yet the master bathroom's aromatherapy bath mode switches on. Ryan drives home, slips inside with a baseball bat, and finds Chloe waiting in a towel, claiming she flew back early to surprise him. The sandalwood bath oil tells another story: she smells only of her everyday body wash, and the cycle ended just as he reached the gate. Whoever soaked in his tub is still inside.

A thud from the walk-in closet, a hastily offered collectible figure, and a lipstick smudge on its collar deepen his doubt, while the smart-home alerts keep firing and the cameras show no one at the door. Then the guard calls: a shirtless man has entered using Ryan's house number. Ryan abandons his train and races home through traffic, chest tight with pain, toward the truth waiting behind his own front door.