Tiliard is a metropolis carved into the stump of an ancient tree. In its canopy, the pampered elite warp minds with toxic perfume; in its roots, gangs of exterminators hunt a colossal worm with an appetite for beauty.
Guy Moulène, a young man working as an exterminator to keep his sister Tyro out of debt, hunts the vermin infecting the city. On a routine mission, his team comes across a monster never mentioned in their exterminators' manual: a streetcar-sized venomous centipede nesting beneath the opera house, digesting the city from the sewers to the opera houses and reshaping its future with every bite.
In parallel, a woman named Aster is caught up in mounting intrigue involving the city's Grand Marshal and Laurel Chancellor, and the arrival of a stranger named Mallory vant Passand. A story of civil war, theatre, and a society wedding; of poverty, art, and dictatorship; of chemical warfare and many kinds of love.