After hearing rumors of a magical healer named Emmanuel this demon attempted to find him and give him to Crowley for a reward. This demon found Emmanuel's wife Daphne and held her hostage in her home.
Dean later sees through this lie after seeing Daphne tied up through the window. The demon attacks Dean but is killed when Dean stabs him with the Demon-Killing Knife. The real Emmanuel arrives seconds later and is revealed to be Castiel who has amnesia.