Danny has recently gained ghostly powers and is still learning to use them. Sam has convinced the school to change its lunch menu to one that suits her ultra-recyclo-vegetarian tastes, thus angering the students and a ghostly lunch lady.
Danny starts "possessing" Dash to get back at him for being mean. This attracts Poindexter, the ghost of a kid who punishes school bullies. Seeing what Danny's doing to Dash, Poindexter thinks Danny is a bully, too!
Danny gets caught by law enforcer ghost Walker in the ghost zone and sentence to spend 1000 years in prison alongside with his old foes, all the while facing the possibility of his parents getting divorced!
When Sam hears about the new Goth circus, Circus Gothica, her overprotective, over peppy parents forbid her. She still goes, and discovers the ringmaster, Freakshow, uses a staff that control ghosts and has come to add Danny Phantom to his employment.
All the adults in Amity Park are being kidnapped by ghost pirate child Youngblood and his helper, Ember McLain, so it's up to Danny and the other kids of Amity to work together to fight back for their parents.
Danny is sick and tired of his human life messing with his ghost life, so he splits himself in two using the Fenton Ghost Catcher, while he lets his ghost self handle his superheroic duties while his human self goofs off. However, the two must find a way to work together when Technus comes to cause trouble.
Danny's friends and family think he is going crazy when he claims he's seeing a ghost that no one else can see. Jazz decides on a vacation for the whole Fenton family, but Danny aims to show her the ghost he is seeing really exist and is not just in his mind.
Danny and Valerie's romance comes full circle as they start dating, much to Sam's jealousy. Technus seems to be pushing the two together in order to keep Danny from interfering with his latest plan for global domination.
While Danny is supposed to be getting in shape, he, Dash, and Skulker are shrunk by Jack's Fenton Crammer, which also slowly takes away Danny's ghost powers! Now Danny and Dash must rely on their natural physical abilities to get to the Emergency Ops Center and reverse the shrinkage before Skulker and his brand new fully-powered ecto-skeleton catch up to them.
Sam enters her school's beauty pageant to display her utter disgust for it, only for her to be crowned the winner. Little does she realize this is all a ploy from Dora the Dragon Ghost to find a wife for her arrogant brother, Prince Aragon.
Tucker's campaign to run for school president goes wrong when no one pays attention to him, including his friends. Fate shines upon him when he meets a mummy ghost who offers him a septer that'll give him an edge, but could there be more than meets the eye?
When Vlad receives Ecto-Acne again, he gets Danny to help by infecting his friends with the same illness. Danny begs Clockwork to let him travel to the past to a world where Vlad Plasmius does not exist. When he succeeds, Danny ends up in an alternate world where his mother has married Vlad and his father, Jack, is a bitter half ghost himself!
Danny, Tucker, and Sam are getting ready for summer vacation, but when Freakshow arrives and kidnaps their parents, they must find the Reality Gems for The Reality Gauntlet in order to save them, and in the chaos, Danny's secret identity is revealed to everyone!
After a fight with their respective boyfriends, Kitty and Ember, along with Spectra team up and rid all the men from Amity Park. With Danny out on a fishing trip with his father (where he gets frequent disturbances from Skulker), Jazz, Sam, and Maddie must work together to get rid of the Ghostly Trio.
With the weather creating ghost, Vortex, Vlad brings rain over the drought Amity Park is suffering through, but plans backfire when Vortex rebels and attacks the entire world and Danny, affecting him by giving him weather powers of his own that shifts with his every changing emotion.
Amorpho takes on the form of Danny himself when he finds the ghost boy stealing his spotlight for attention. However, both he and Danny are caught in a complete mess of events when a Fenton machine causes Danny to remain in his ghost form and Amorpho's powers to decrease as well.
The Guys in White buy out Fenton Works causing the family to live a life of wealth and luxury. However Sam and Tucker must convince a now-snobbish Danny to stop the Guys in White from destroying the Ghost Zone.
Tired of being taken less then serious, Box Ghost steals Pandora's Box and creates an unholy tyrant of evil from it in Amity Park, himself finally posing a level of threat for Danny who must seek Pandora's help.
Danny wakes up from a dream, destroying a unique helmet placed on his head. He finds the entire town of Amity Park is under the same ailment due to Nocturne, the ghost of sleep who is sucking up their dreams to increase in power. Danny must wake his friends and sister up in order to stop this madness.
A camping trip with Danny's classmates goes bust when campers are slowly being kidnapped by monsters, causing Danny and his friends to investigate the matter, ultimately running into an old friend in the process.
Vlad commissions the Masters Blasters to humiliate and outdo Danny Phantom, which works all too well as Danny strips himself of his powers and retires as Danny Phantom. Danny then tries to live his life as a normal human, but a hero is needed when a deadly asteroid is about to obliterate the Earth (and, by default, the Ghost Zone). Vlad Masters reveals himself to the world as Vlad Plasmius and attempts to stop the asteroid in exchange for world domination, but fails. Danny must now team up with the Ghost Zone denizens to make the planet intangible so that the asteroid will only pass through the planet. Will his enemies become friends, despite their life-long differences?