The Starless Sea
Why it's similar
Morgenstern's own second novel is the most obvious follow-up, and it earns the top spot because nobody else writes quite like this. The Starless Sea follows a graduate student who discovers a mysterious book that contains a story from his own childhood. Searching for answers, he finds a hidden underground library that houses a world built from stories, keys, bees, and honey. The atmosphere is thick enough to swim through. Where The Night Circus used a traveling circus as its enchanted setting, The Starless Sea uses a library beneath the earth.
Both books treat physical spaces as characters in their own right, described with the same loving, sensory detail you would use for a person. The romance here runs quieter and stranger than Celia and Marco's, but it carries the same ache. I think readers who loved The Night Circus for its dream logic and its willingness to let mystery remain mysterious will find even more of that here. Morgenstern pushed her own style further, and the result is a book that asks what we owe to the stories that shaped us.