Season 1

Suspended from her normal duty, Officer Kate Benson is recruited by Special Unit Two (SU2) for a temporary assignment. Mature gargoyles that have been hibernating (on churches in Europe) have awoken and are collecting food (people) to feed to their eggs which have been incubating for 17 years. The victims are being kept alive until the eggs hatch. SU2 has 24 hours to track down the gargoyles and destroy the nest before the mass hatching occurs.

Werewolves, scientifically known as lycanthhropes, (thropes) are roaming the city killing innocent people who just happen to be in the wrong place at the wrong time. But these Links' superhuman senses and strength, and their ability to blend in with the human population while not in wolf form, make the detectives' work quite intense...

On the way to an exhibit at the museum, a mummy is revived by an electrical storm. However, this is no ordinary mummy, it was the most feared Japanese Samurai warrior that ever lived. The mummy wants all the things promised to him in the afterlife. To achieve this the mummy must collect everything he was entombed with, including three female concubines. He has the first two women and targets Kate as the third. For Nick, what started out as a standard Link investigation now becomes a rescue mission.

Spider man, spider man...only this time it's women. Kate and Nick must track down and terminate an infestation of spider-women who find Chicago's single men a delicacy. It gets even stickier when Nick takes a personal interest in protecting the only witness in the case.

A Link is formed out of fat from liposuction patients from a plastic surgery clinic. The link kills the plastic surgeon when he gets in the way of the link's food supply and then disappears into the Chicago water system. The first detective on the scene is Rich Talridge, who was O'Malley's first partner before Nick was picked for SU2. Rich doesn't like that the case has been handed over to SU2 and tries to solve it himself which gets him in trouble. Kate and Nick and the rest of SU2 are left trying to track and get rid of the "Fat Link" before it kills again.

Some water Links, nicknamed Mermen, from two years ago have reappeared and are victimizing young women. The merman emits a high pitched sound which temporarily paralyzes the victim thus making it where the merman can empty the victim of their soul. This leaves the victim in a semi-vegetative state. The catch is that it only works on virgins. A tie-in to the story is that Kate's younger sister is visiting and dating a rather mysterious guy. Kate starts to suspect the guy may also be a merman and that her sister may be the next victim.