She’s playing Red John!!
Wait, that came out wrong. What I meant to say is she’s connected to Red John, the infamous serial killer who took the life of P-Jane’s wife and child.
Let me back up: Sources confirm to me exclusively that Alicia Witt (of Cybill and Law & Order: Criminal Intent fame) will guest star in the season finale of The Mentalist as Rosalind Harker, a luminously beautiful piano player who used to date the madman, the myth, the legend known as Red John.
OMG, this is just the break Simon Baker’s master observationist was looking for, right?! Well, kinda. You see, Rosalind isn’t able to… The thing is… What I’m trying to say is… It’s a big ol’ twist, dammit!