Denzel Quincy Crocker, a.k.a. Mr. Crocker (voiced by Carlos Alazraqui), is a gray skinned, hunchbacked man (with ears on his neck), Timmy's 40-year old fairy-obsessed teacher, and the second main antagonist in The Fairly OddParents. At the beginning of the series Crocker is notably more fair and less fairy obsessed. He is often depicted as a seemingly insane person. He correctly suspects that Timmy has fairy godparents of his own, and is often able to tell what Timmy has wished for by the smallest, most irrelevant clue. His unshakable belief in fairy godparents leads to his being viewed as mentally ill by other adults. Whenever he mentions fairies, (mostly shouting "Fairy godparents!") he spasms uncontrollably, which has been a running gag and occasionally causes him to be injured. Crocker thoroughly enjoys giving Timmy F's on all his class assignments, and often does so even when Timmy is correct just to get pleasure out of it.
It has been revealed that Crocker is Cosmo and Wanda's ex-godson and is in their fairy godchild hall of fame, in the episode "The Origin of Denzel Crocker"; Timmy's attempt to uncover the reason for Crocker's attitude in his time by travelling into the past accidentally caused Crocker's future hostility as he accidentally exposed Crocker's fairies and resulted in Crocker being chased by an angry mob. His only identified relatives are his mother, Delores Day Crocker, his Canadian genie-paranoid uncle Albert, his 16-year-old step-dad Ricky, his grandfather who was turned into a grandfather clock and his probable ancestor the witch-paranoid Alden Bitterroot, who is a witch. Crocker was once a hero and had his own honorary day on March 15, 1972, before it was ruined by Timmy, who had traveled back in time (although, before that happened, it would appear that Cosmo initially ruined it for Crocker).
Ironically, Crocker serves as the main power source for all of the fairy magic. His belief is so strong that it was used to power the Big Wand (the source of all the magic in Fairy World); thus, it was catastrophic when his therapist hypnotized him into not believing in fairies.
Crocker served as the primary antagonist of Abra-Catastrophe! and the first film of The Jimmy Timmy Power Hour series. Another running gag for him is whenever he (or anybody else) enters his "Crocker Cave", they fall hard on the floor after falling through a hole in the ceiling and move a mattress into place beneath the hole, but it somehow always ends up moved out of place again.