Fringe episode 13 is called "The Transformation".
A mysterious virus emerges and and agents are forced to go undercover on Fringe!
When the Fringe Division delves into another bizarre occurrence aboard an international jumbo jet, freakish remains are discovered at the crash site. Memories tip the team toward some promising leads, but the bigger picture and mysterious threat eludes them. With limited options and insufficient intelligence, Olivia and Peter go undercover in the all-new “The Transformation” episode of FRINGE.