Can we detect gravitational waves without knowing what they look like?

Most gravitational wave searches need a template — a prediction of exactly what the signal looks like. This framework skips that requirement, modeling any localized source using a flexible Fourier expansion with a Lorentzian prior that automatically captures the signal's dominant frequency. Tested on simulated pulsar timing data, it recovers both sky location and signal properties without being blind-sided by unexpected sources like cosmic string bursts or exotic compact binaries.