This Tuesday at 9 pm/ET, Fox's Fringe will shed light on one of its deepest and darkest mysteries: Is FBI agent John Scott truly dead and existing only in Olivia's conscience, or might he actually be alive?

Mark Valley stopped by TVGuide.com to address that pointed question (at the 45-second mark in this video), as well as preview more about this week's episode, "The Transformation."

"We're going to find out a little bit more about who [John] was working for, and his feelings for Olivia," Valley shared.

Other topics touched on during this sit-down include John's true feelings for Olivia, and whether Agent Scott was (is?) good or bad.

Valley also shares the surprising "secret recipe" for creating translucent skin he sported in the pilot and makes a case for former Boston Legal cast mate William Shatner to stop by the sci-fi series.

At the very end of the interview, Valley offers up the burning questions he would like to see Fringe answer.  

Additional reporting by Mickey O'Connor and Erin Fox

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