When a man mysteriously dies by an invisible force, his body rapidly begins turning ghostly white. The Fringe team learns that this is not an isolated incident, and there’s evidence that links the predator to someone who passed away with an unknown genetic disorder. Meanwhile, Olivia suffers from migraines.
"Wallflower" is the seventh episode of the fourth season of the Fox science-fiction drama television series Fringe, and the series' 72nd episode overall. "Wallflower" served as the show's mid-season finale, as it was the last to air in 2011; the next installment was broadcast on January 13, 2012.
