Who is Laura Linney playing in HBO's Lanterns?!

Rumors of Laura Linney joining HBO Lanterns had been swirling for a while, but nothing was confirmed until we all saw the second teaser for the show, in which she showed up as an unnamed character. When the rumors happened, we all expected that she was playing Carol Ferris. There are also people out there that believe she is a Guardian of the Universe. She's not brunette. She doesn't have blue skin. Could she be someone else entirely?? Join Ralph on this episode and try to see if there are any clues to who she might be playing.