Ars Opus was a BFF-1 bulk freighter that was carrying R2-series astromech droids to the Imperial-class Star Destroyer Invincible when it apparently broke down in the Rudrig system. The Ars Opus was discovered by a Rebel R-22 Spearhead reconnaissance flight and, following a recent warning from Ordnance and Supply about a shortage of astromech droids, the Rebels decided to mount a capture operation.