Odo falls in love during an investigation.
In Quark's bar Odo meets Arissa, who is soon arrested trying to break into the station's computer. She was waiting for Tauvid Rem, who has been murdered. Arissa admits she works for Draim of the Orion Syndicate and wants out, and that Tauvid had a data crystal she was seeking. Odo hides her in his quarters as Dax and O'Brien try to break the crystal's encryption, and the two become lovers.
Arissa secretly offers the crystal to Draim for her life, but his killers plan to murder her. An Idanian official tells Odo that Arissa is really an Idanian agent whose memories were erased for an undercover mission, and the crystal holds them. Odo saves her, her memories and true appearance are restored, and she returns to her husband. Styled as film noir, the fifth-season episode gives Odo his first physical romance and leaves him heartbroken.