Cat and Mouse

E1

A shocking online video brings together a widespread internet group of animal lovers out for justice. Their target, meanwhile, has more horrors planned.

Killing for Clicks

E2

A new video pushes panic to the next level, galvanizing the "internet nerds" to intensify their own painstaking investigation as police join the hunt.

Closing the Net

E3

With the killer's identity -- and twisted motives -- revealed, the group finds more key clues as the global police manhunt reaches a fever pitch.