The Colours of Madeleine Books in Order

The Colours of Madeleine books begin with one of Moriarty's best premises: a girl in Cambridge and a boy in another world start writing to each other through a crack between universes. From there, the series grows into a portal fantasy with mystery, political strain, family drama, and a surprisingly grounded emotional core.

Madeleine Tully lives in Cambridge, England, in the World, which is our world, more or less. She is clever, restless, and trying to hold herself together while her mother is ill. Elliot Baranski lives in Bonfire, in the Farms of the Kingdom of Cello. His world runs on stranger logic. Seasons roam. Bells warn of attacks from dangerous Colours. People worry about cracks between worlds, because cracks are supposed to be reported and closed.

The letters change everything.

At first, the correspondence feels impossible and secret, which is exactly what makes it so compelling. Madeleine and Elliot are dealing with private worries, a sick mother, a missing father, and the usual awkwardness of being young, and then suddenly they have each other. Their messages are funny, wary, practical, and often deeply kind. The relationship between their voices is the heart of the series, even as the plot keeps widening around them.

Cello is not a tidy fantasy kingdom.

As the trilogy moves through The Cracks in the Kingdom and A Tangle of Gold, the stakes expand from two teenagers' lives to the fate of an entire realm. Princess Ko is trying to keep a government steady while royals disappear. The Royal Youth Alliance forms to investigate what adults cannot or will not fix. Elliot's search for his father and Madeleine's link to Cello start feeding into a much bigger problem, involving missing people, political unrest, mounting danger, and the risk of war.

What makes the series stand out is its sense of scale. Moriarty can write a kingdom in crisis, but she is just as interested in the awkwardness of a letter, a family dinner, or a bad day at school. There is plenty of worldbuilding here, but it never feels like homework. Cello has personality. So does the World. Science, magic, and bureaucracy rub up against each other in odd and memorable ways. These books are best read in order, because the mysteries build on one another and the emotional payoff gets richer as the connection between the two worlds deepens.