Are there nude beaches anywhere around New York? There must be a nudist society or something. So maybe a nudist is plotting to murder their spouse and Reese has to show up and save them... naked. Would love it if Carter was around for the end of the case, or maybe called in to look over the surveillance video. (Bonus: set it during early S1 and have Carter pursuing the "man in the suit"... out of the suit.)
Carter/Reese, a case requires nudity