Zero Time Dilemma's newest concept art image depicts a handsome and mysterious man known as "Participant 1":

While little is known about him, his expression is rather crafty and a bit menacing (not to mention the intensity of his eyes). It makes you wonder if he's a jerk with a heart of gold or a villain through and through.

It's be interesting to see the next participant, as we're still missing numbers 3, 4, 5, 8 and possibly 0