In the Criminal Minds Season 13 episode " The Dance of Love " (S13E18), the BAU pursues a serial killer in Chicago who murders women and leaves red roses, while David Rossi handles a personal case involving his ex-wife's daughter. The team tracks down the killer, who is revealed to be the wife of their original suspect, and Agent Matt Simmons resolves the hostage crisis by appealing to her delusions. Concurrently, Rossi uses his investigative skills to expose a con artist trying to marry Krystall’s daughter.
You can find more detailed summaries of this episode on Criminal Minds Wiki and TV Fanatic . [S13E18] The Dance of Love