Spreadsheets are spells. Dragons are unionized. Nachos are a sacrament. Buckle up.

When actuary Ptolemy “Tolly” Blackthorne inherits his grandmother’s scarf—a knitted, contraband probability anchor—he also inherits her secret: a multi-dimensional dragon-racing circuit that runs on risk, wit, and a frankly alarming amount of nacho cheese. Tolly’s talent for modeling disaster was supposed to keep him safe; instead it drafts him into a portal-hopping season where vertical Niagara roars upward, magma judges enforce “Fun is mandatory,” and Mars rovers form a picket line for better dental.

With a knitting-needle-wielding grandma, a sphinx librarian who demands inside voices, a beatbox legend who drops bass on probability, and a chorus of dangerously sincere Chads, Tolly learns the one formula that matters: chaos + order = meaning. But the circuit has a parasite—Mundungus Sweetwater, the audit made flesh—hungry to turn every choice into a void. To win, Tolly must turn spreadsheets into poetry, enemies into acknowledged footnotes, and a scarf into a future where dragons get to choose what they are for.

For listeners of Douglas Adams, Terry Pratchett, and anyone who’s ever believed a to-do list could save the world—Grandma’s Illegal Dragon Racing Circuit is a big-hearted, high-velocity romp about variance, agency, and why no one is a rounding error.