Thirty-something Lauren has been leading a steady, enjoyable single life: great friends, good job, and a nice flat in south-east London, until, one night, she comes back from a party to find a stranger in her home. His name is Michael. He's attractive, sweet, and, according to him, her friends, and the pictures on her walls, he's Lauren's husband.

Just as Lauren is trying to figure out how she could be married to someone she can't remember meeting, Michael climbs up into the attic to change a lightbulb and abruptly disappears. In his place, a new man climbs down, and a new, slightly altered life reforms around her.

Lauren quickly realizes that her attic can somehow--incredibly--supply her with endless iterations of lives and partners. Cycling through marriages--sometimes lasting weeks, sometimes less than five minutes--Lauren grapples with her fate. If swapping husbands is as easy as changing a lightbulb, when do you know you've found the right one? How do you recognize what's good, or what simple happiness feels like, in a world that demands constant optimization with one more search or swipe left?