A dentist tends a dragon's teeth while a war rages outside, and somehow this is the most urgent thing happening. Bell emerges from a cavity like a resurrection nobody wanted, and the show never explains why, it just moves forward with the certainty of something that knows exactly what it's doing. The animation folds war and mythology into dental work until you stop asking which one matters and just watch it all burn and grow at once.
Nonoko Kishii has just become a dragon dentist in Dragon Country. Her job is to guard the nation's protector, an ancient dragon bound to it by a pact, from the cavity bacteria that can leave even such a powerful creature useless. To join the dentists she had to witness her own future death and accept it. As fighting with the neighboring country grows fiercer, she finds Bell, an unconscious boy soldier from the enemy side, on the dragon's tooth. Killed by his own men and brought back by the dragon, he is an omen that legend says comes before a great disaster. Placed in Nonoko's care as a trainee, he faces battle after battle alongside her as both learn to accept their fate.