Jack once lived in Boston with his mother, Rose Davids, and pet dog Spencer. He loved making vlogs and uploading videos of skateboarding tricks and other things together with Spencer and overall lived a happy life in the city until his mother announced they were moving to Newbury, a small southern town. Jack was horrified at the thought of leaving his home to move to the small town, which he referred to as "that backwater". A week after that Jack received many videos about paranormal activity from an unknown person in Newbury and one week after that Spencer was killed in a traffic accident due to his habit of chasing cars, leaving Jack even more heartbroken.
The week after Spencer's death, Jack and his mother moved to Newbury where his mother became the principal of Newbury High School while Jack was bullied or ignored due to being the son of the principal and his classmates dismissed his vlog as him "talking a lot of hot air online" although Jack did try to fit in by making crazy videos for his vlog. Later that day, he met a girl named Parker at lunch break, who revealed to him that she was the stranger from Newbury who sent him all the videos. Parker then showed him around the school and introduced him to the janitor Douglas and later J.B.. Parker and J.B. then revealed to Jack that they were Ghost Hunter who captured ghosts who wreak havoc in their town and offered Jack to join them, J.B. also gave him an app that allowed Jack to see Spencer, who had become a ghost and had been following Jack since his death.
Parker and Jack are sent to Newbury High School after getting reports of high levels of Ghost activity. When they enter, they spot Douglas who is possessed by a Ghost. They shoot him down, releasing the Ghost from inside of him and capturing it.
Soon, Jack takes off exploring after running away from Grandpa Sam. He enters a room where a Ghost is hiding and gets possessed by it. Fortunately, he is saved by Spencer who pulls on the Ghost.
After Parker got a notification by J.B., they try to exit but are surrounded by Ghosts. They use the elevator to escape, but the elevator malfunctions, sending the Hunters tumbling down.
Eventually, they find Mr. Nibs, who pops out of the stuffed teddy bear. He attacks the Hunters; however, they are able to escape with the help of Douglas. They head outside where they are greeted by J.B. in the Paranormal Intercept Bus 3000. J.B. prepares to shoot Mr. Nibs down with Jack and Parker joining in.
Jack is live streaming on BOO-Tube and introduces the Ghost Hunters to his fans. Soon, he enters Newbury Graveyard along with Parker, Douglas, and Spencer.
He continues to live-stream his adventure, but it causes him trouble as he falls behind the rest of the group. Jack tries to catch up but trips on vines holding a key. The key then floats in the air and unlocks the Mausoleum, spewing green fog from its entrance. Jack begins to panic at the situation and uses his phone to scan for Ghosts, but is confronted by Mamali.
Frightened and petrified, Jack tries to use his phone for defense, but his phone was out of battery. He then tries to flee, but the branches of a tree capture him. She sings him a lullaby much to his pleasure and attempts to devour Jack, but Parker shoots Mamali with her phone.
Parker and Douglas are able to save Jack, so they flee after locking up Mamali. J.B. asked about their success and an outraged Parker explains that Jack's phone died. J.B. then points out that Jack's phone is still being used although he's using Parker's phone. She then tries to reclaim her phone as J.B. drives off.
While Jack is rapping about how great of a Ghost Hunters he is, Parker stops him and tells him that she's the better Ghost Hunter. They take a vote and everyone agrees that Parker is the best.
When they get off the bus to investigate, Jack brainstorms on all the things he's better at than Parker. He soon realizes he's better at swimming when Parker gets captured by Archibald. He gloats at the moment but realizes he has to save her.
When they reach the surface, the Hunters are immediately attacked by the Shrimp Boat, so they swim to the docks. While they are running away, they shoot at the oncoming boat and free Captain Jonas and Jonas Jr. from their possessions.
All four of them make it inside the Paranormal Intercept Bus 3000. Later, Parker thanks Jack for saving her as they both make amends for their previous troubles.
Parker and Jack are debating are walking down the beach and debating whether cats or dogs are better. Jack shows why dogs are better by calling Spencer's name without bacon. He reappears and runs away from Jack after smelling bacon.
The Hunters head to Shrimp Shack where Spencer entered. Parker notices that it's abandoned and shouldn't enter, but Jack pulls on the wood and they are able to enter the restaurant.
Jack searches for Spencer but is unable to find him. Parker suggests that they should get J.B. after seeing an eerie photo, but Jack doesn't want to give up. All of a sudden, the Hunters encounter Anomalo who holds Spencer hostage. He challenges them to a bacon eating contest which they are forced to accept or else they would be killed.
Anomalo takes an early lead in the contest due to him having a plethora of arms. Parker and Jack struggle to keep up, but Jack hears Spencer's wince and offers him a piece of bacon. He realizes that he can feed Spencer, who is underneath the table, bacon without Anomalo noticing. Parker follows his suit, and before Anomalo could finish, Parker and Jack finished first.
However, Anomalo refused to let them leave and instead attacks the Hunters. Parker ends up getting surrounded by Anomalo's knives, but Jack calls for Spencer, who is still being held by Anomalo. Spencer bites Anomalo giving Parker a chance to capture Anomalo onto her phone.
Parker and Jack are at Newbury Railroad Station to pick up an important package for J.B. Both discuss what the package might be and Jack thinks it's a super battery for their phones. They then place a bet with the loser having to do the others homework.
When the train arrives, he argues with Parker on what they package is. All of a sudden, The Bawa appears out of nowhere and possesses the train. The Hunters, still on the train, are taken up as well. While up in the air, they fight Ghosts before The Bawa lets go of the train and repossess it.
Parker catches sight of El Fuego's Stunt Truck and is able to land the package safely. They arrive back at J.B.'s Ghost Lab where they realize the package is only a coffee machine. Since they both lost the bet, they suggested doing each other's homework, but J.B. tells them that the machine also does their homework.
Jack is about to vomit after drinking one hundred Lime Slushies. He is able to find a Portable Toilet and cuts Nanna in order to use it.
After using it, he caught sight the Portable Toilet is shaking and after further investigation, he realizes he has created Spewer who attacks Jack. Jack attempts to fight back but is forced to dodge the Gloom and retreat.
Eventually, J.B. is able to save them by destroying Spewer. Parker and Jack come over to congratulate her, but she heads over to Sweet Sally and promises to fix her up.
Jack is at Newbury High School and is proud of the video he uploaded. While he is walking to class, J.B. calls to inform him that Parker was turned into a Gloombie. By the time Jack looks at Parker, she begins to attack and Jack hides in a locker. J.B. tells him that the only way to free Parker is to make her laugh.
Jack tries many ideas to make Parker laugh, but none of them work. It isn't until he realizes Parker is a cat person that he is able to help Parker return to normal.
While chasing Dwayne and Joey, Jack was inside Sweet Sally taking selfies. However, when Parker and Jack were shooting at the Gloombies, Samuel Mason appeared and destroyed a bridge allowing the bikers to escape.
Later, after Jack captured Mason, Parker and Jack criticized Douglas's outdated phone until Parker said that the phone was almost as old as J.B., causing her to glare at Parker while Douglas and Jack laughed and Parker questions them on what she said.
While inside J.B.'s Lab, Jack is live-streaming the entire event and doesn't pay attention as he accidentally touches the Erlenmeyer Flask which releases Dr. Drewell. The mad scientist begins attacking and the Blaster on Jack's phone does nothing to stop him from possessing objects. When Dr. Drewell snatches Jack's phone, he tells him to get back into the bottle but is immediately corrected by Dr. Drewell and J.B.
The two scientist begin to flirt together much to the agreement of Parker and Jack. While they are talking about Lady E, Jack asks about her and Dr. Drewell reveals the plans that she has before leaving.
Jack and the rest of the Ghost Hunters storm Newbury High School. He chases Mamali away before assisting Parker in capturing Mr. Nibs. However, they are too late as Lady E. is released from her portrait. In an effort to save Newbury, Douglas shields Lady E. from the light of the Blood Moon and forces her back into The Hidden Side, but Douglas also enters the unknown realm.
When morning breaks, the Hunters are about to leave until Douglas returns as a skeleton. He warns them that Lady E. will return at some point.
Jack and Parker's parents head over to Newbury High School to discuss their missed assignment. When they arrive, Rose asks about his troubles, and Jack gets angry with her. When they arrive in Mr. Clarke's room, he turns into a Gloombie and spews Gloom on the group. Parker and Jack avoid it, but their parents are possessed.
After realizing Mamali was behind this, they chase after her, but she steals Jack's phone and gets chased by the Gloombies.
Sometime later when Parker is able to capture Mamali, she throws down Jack's phone and they are able to free their parents. They asked what happened, and they lied by saying that they received detention.