Given the disappointing sales of TRU, we're going to guess that quite a few haven't played the title yet. As this playable character is a spoiler, we'll place that info after the break.
Underworld's DLC producer Rob Rosenberg reveals the new character will be Lara's doppelganger. Sure, that's kind of a cop-out, but Rosenberg tells Eurogamer that Lara's Shadow will have gameplay that takes advantage of the doppelganger's strength and agility. Each of the DLC episodes should take between "three and six hours to finish."