Erikachristensen_parenthood_290 All weekend long, "Lie to Me" showrunner Shawn Ryan has been teasing the casting of the sophomore series' first major second season guest star via his Twitter account.

It started on Friday with … "Just cast our big guest role for the first ep of Lie To Me. Our multiple personality disorder victim will be played by the very talented E .."

Ten hours later: "Still figuring out twitter. Apparently last announcement got cut off. Guest actress playing the multiple personality disorder girl is Er.."

Eleven hours after that: "Okay, this is getting frustrating! My messages seem to get cut off right before I can reveal the Lie To Me guest actress name which is Eri .. "

From the initial letter "E" we were guessing Erica, Erin or Erika.

The Twitter from the wee hours of this morning pretty much solidified our best guess: "Table Read of 1st episode of Lie To Me is today. Filming begins on Tuesday. Have I mentioned yet that our big guest star in Ep. 1 is Erik .."

Based on that "k" we're going with Erika Christensen, who a) has a history with FOX having been on "That '70s Show" and, b) recently had her schedule open up with "Parenthood" being pushed to midseason.

What do you think? Is it Erika Christensen? Who else could it be?

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