Seventeen-year-old Emlin is about to become a fully-fledged crafter of dragon-inspired stained glass. Then her mother is murdered following a mysterious, nighttime trip to the palace.

The Watch hasn't a clue who the murderer is, so Emlin vows to find the killer herself. A series of attacks on her and her sister glassmakers makes her suspect that the attacker is keen to destroy the glass crafthouse, an event that would weaken the island's connection to its dragon and leave it vulnerable.

Dogged by a curious if charming scholar who can't keep his nose out of her business, she questions anyone her mother saw in the days before her death, finds herself breaking dragon-given laws, and learns things about her mother that call into question whether she'll ever become a glassmaker-assuming she lives long enough.