Sometimes cold cases remain frozen unless an experienced private eye leads the investigation to solve the mystery. Age is nothing, but a number and sometimes the experienced PI arrives in the form of an underaged sleuth.

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Teenage detectives like Enola Holmes use their wit, imagination and lessons from mentors to get to the bottom of the mystery afoot. Their underrated brilliance allows them to crack cold cases that have left adult authorities bewildered.

Harriet the Spy

Harriet the Spy

With aspirations of becoming a writer, Harriet seeks inspiration by spying on everyone in her neighborhood in Harriet the Spy. The snoop documents her findings her journal.

After her classmates discover her secret journal, Harriet’s life becomes a nightmare because of their pranks. The bullying enables Harriet to sharpen her sifting skills. She digs up exclusive dirt on each classmate and uses the secret for vengeful tactics.

The Kid Detective

The Kid Detective

Abe Applebaum is highly regarded in his town for his work as a detective and is often leaned on by the mayor to solve various crimes in the neighborhood and school. Following the disappearance of his assistant and best friend, Applebaum loses his confidence when the trail on the case grows cold.

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Applebaum’s tenure as the local kid detective in the early part of the film includes exemplary work. The cases of the missing basketball magazines, stolen bikes and a hit-and-run accident are some of his accomplishments. The only case the teenager wasn’t able to immediately solve was case where the culprit reported a kidnapping to cover up his tracks. The detective would eventually snap the smoke and mirrors and uncover the mystery at age thirty-two leaving his track record in The Kid Detective unblemished.

Holly March

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Shane Black’s The Nice Guys is a buddy action mystery movie starring Russell Crowe and Ryan Gosling as private investigators. Ryan Gosling’s character is aided by his daughter, Holly March, who helps her father uncover clues throughout the comedy thriller.

The thirteen-year-old Holly March serves as her father’s chauffeur during his cases. Despite her inexperience, she excels in interrogation and her questioning leads her to Amelia, the only lead in the case. Holly’s intelligence propels her father and his partner to visit the LA Auto Show where a missing film is being housed, and her idea exposes the dirty dealings of the villains in the movie.

Devon Butler

Devon Butler_Cop and a Half

After witnessing a murder in Cop & ½, Devon Butler parlays his testimony into an honorary policeman gig. The miniature gumshoe joins forces with a detective played by Burt Reynolds to track down the murderers.

Butler’s immaturity is halted at his height, and he shows more poise than his adult counterparts. The neophyte has a deeper knowledge of the rule book than his partner and Butler’s direction guides the duo to locating the criminals and their uncovering their motives for the murder.

Nancy Drew

Nancy Drew and the Hidden Staircase

In Nancy Drew and the Hidden Staircase, a teenage sleuth moves to a new town and, upon arrival, is thrust into an investigation of a haunted house. Nancy Drew connects the dots between the hauntings and a conspiracy regarding the development of a train line in the town.

The town’s newcomer spoils the villain’s plan to derail the anti-train protest after only a few days on investigative work. With few resources, Nancy Drew uncovers a conspiracy the entire police department couldn’t crack.

The Goonies

The Goonies (1985)

A group of kids discover a map and wanted posters and are tasked with finding a long-lost treasure hidden by a pirate while evading a trio of criminals on the run for murder. Led by their fearless thirteen-year-old sleuth, the Goonies attempt to unlock the hidden location of One-Eyed Willy’s treasure.

In Goonies, the gang located One-Eyed Willie’s treasure and uncovered the secret hideout of the Fratellis. The young crime stoppers uncovered clues that pirates before them could not and by seizing the delinquent Fratellis, the group outshined the local police department.

Scooby-Doo Gang

The Scooby gang
Image Via Warner Bros.

The kids from Mystery Incorporate have been cracking cases since the late 1960s. Scooby-Doo, Shaggy, Velma, Fred, Daphne and Velma have showcased their talents as investigators on various Scooby-Doo cartoon television series and numerous live-action and animated films.

The meddling kids use their unique skill sets to solve difficult crimes. Fred’s leadership, Daphne’s intuition, Velma’s intelligence and Shaggy and Scooby’s favorable fate have allowed the crime-solving teenagers to unmask north of 387 mysteries within the Scooby-Doo media franchise.

Young Sherlock Holmes

Nicholas Rowe in Young Sherlock Holmes

The origins of Sherlock Holmes are displayed in the mystery adventure film Young Sherlock Holmes. The youthful investigator explores a string of deaths linked to hallucinations.

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The adult iteration of Sherlock Holmes is regarded as one of the most brilliant detective minds. This origin story reveals the building blocks that led him on that path. Holmes’ mentor pushes him towards technology and Holmes’ affinity for science and tech pit him at the bleeding edge of fact-finding.

Enola Holmes

Enola Holmes with a bow and arrow in 'Enola Holmes 2.'

Younger sister to Sherlock Holmes, tracking is grafted in Enola Holmes’ DNA. Following in her big brother’s footsteps, the rookie gumshoe occasionally outwits her brother to solve cases in Enola Holmes and Enola Holmes 2.

In the first installment of the franchise, Enola proves to be a proficient investigator after collecting bread crumbs, left behind by her missing mother, that left her older siblings puzzled. In the sequel, she hones her trade and becomes a licensed private investigator and is enlisted for high profile cases while under the age of eighteen.

The Golden Trio

Harry Potter feature

Voldemort’s plan of genocide that would rid the world of muggles was foiled by three children in the Harry Potter series. During the first seven years of their studies at Hogwarts, Harry Potter, Hermione and Ron blew the lid off corruption in the boarding school and the Ministry of Magic.

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Each member of the gang proved instrumental in the discovery of The Dark Lord’s evil plans. Harry’s connection to Voldemort pit him as a mainstay of their investigations, Hermione’s knowledge served as a crucial element while chasing leads and Ron’s bravery would occasionally, push the group towards their maximum potential. The three were minted as Hogwarts go-to mystery solvers.

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