Zack is an ex-government agent turned fairy hunter who seeks to expose the existence of fairies to the U.S. government, much like Mr. Crocker. He is slightly tougher and a bit more serious than Mr. Crocker. He is the equivalent to Denzel Crocker much like Sally is to Timmy. Unlike Denzel Crocker, where he lives with his mother, Zack is independent and lives alone, and it is hinted that he knows Jonathan's dad and keeps him imprisoned in his house.
Zack has black hair and red eyes. He wears a black suit with a belt adorned by yellow lightning.
Zack, Crocker and Vicky plotting to ruin the party