Fringe (2008)

S3E13 Immortality

Returning to the alternate universe, the Fringe Team feels the impact of Colonel Broyles' absence while they pursue a bioterrorist using a flesh-eating insect as a weapon. Simultaneously, alternate Olivia reconnects with her romantic partner, navigating their complex relationship. Meanwhile, Walternate is resolute in his mission to protect his world, yet he confronts moral boundaries he is unwilling to breach, complicating his plans further.