Today's Thursday installment of Whodunit has us combing through the Gatecrasher archives to figure out which celebrity duo started out as a three-way, presumably with one of the megawatt boldfacers making a cameo as the special guest star.

So which twosome was originally a threesome? Which Hollywooders would rather screen their partners through intensive orgies than deal with the meat-market of the online dating scene? Send in your best guesses, crackpot theories and most imaginative tips if you think you know Whodunit.

Which megastar couple, whose torrid fling was first flagged in this column, consummated their acquaintance with a ménage à trois?