When Cupid's 'love potion' causes a hangin' judge to start setting high-end criminals free, it's up to Kate and Carl to get an on-the-lam Cupid back to Chicago to reverse his potion's' effect on both the judge and a transformed Nick, whose newfound propensity for seeing the good in everyone begins to wear thin on his colleagues.
The Scarecrow, a particularly noxious Link, is inadvertently unearthed and loves nothing more than the fear and mayhem he creates by reading - and exploiting - the "fear center" in every Chicagoan's subconscious. As the city degenerates into mass hysteria, Nick and Kate learn that to defeat the Scarecrow, they must first deal with all their own fears and phobias
Cajoled by Nick into attending her high school reunion, Kate is forced to relive the humiliation of how she ruined her graduation 10 years earlier by taking over the ceremony and hysterically insisting that Links lived in the walls of the school. Acting as her escort to the reunion, Nick helps Kate redeem her reputation when the Links return and attempt to massacre her classmates.
A Link so monumentally evil that his name has been lost to history reappears on Halloween, the one night of the year when Links can roam with impunity. The confrontation between the Link and Nick is made all the more personal - and lethal - as it is the villain responsible for the death of Nick's former partner. The mysterious Link is bringing the corpses of serial killers back to life so they can carry out his plan to assume leadership of all Links.
A fabulously wealthy - and beautiful - cosmetics executive is Nick and Kate's key suspect after a 19-year-old male model is found mysteriously dead of old age. Using Nick as bait, the SU2 detectives must prove the glamorous tycoon is a witch who has lived for centuries by literally sucking the youth out of her victims to keep herself young.
A Sandman Link takes over the bodies of everyday people when they sleep and has them act out their wildest subconscious fantasies. Kate falls asleep while quarantining an area and the Sandman enters her. Kate becomes dangerous under the Sandman's attraction and the team must destroy it before it's too late for Kate.