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Case closed

青山 剛昌 [Gōshō Aoyama]

Cover of Case closed

Case closed

Age Rating, Reading Level & Content Guide

by 青山 剛昌 [Gōshō Aoyama]

Reading Level 4-5 9MP Ages 9-12 Matched

The text is written at a 4th grade reading level, the subject matter is intended for middle graders (ages 9–12), and the content has moderate intensity with some emotionally heavy themes.

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About This Book

Conan watches closely as two shadowy men exchange a secret package, but suddenly, they capture him! A mysterious poison shrinks him into a child’s body, yet his brilliant mind stays sharp. Now, trapped in a kid’s form, Conan races to solve crimes and uncover the truth behind the secret organization—can he catch the thief and murderer before it’s too late?

Quick Assessment

This graphic novel follows Jimmy Kudo, a talented high school detective who is transformed into a child after being targeted by a mysterious organization. Aimed at ages 9-12, it combines mystery, suspense, and detective work with some mild peril and complex themes around identity and deception. Parents should note the presence of crime, mild violence, and suspenseful situations, but the story remains appropriate for middle-grade readers.

Why we rated Case closed 9MP

Case closed is written at a Level 4-5 reading level across 192 pages. Strong independent readers around grade 5.5 can typically handle this book on their own; with parent or teacher support, Case closed works for readers up to grade 6.5.

We rate Case closed as 9MP ("Moderate — Physical") because the content sits in the "Moderate" range — moderate conflict that may involve loss, scary scenes, or interpersonal stakes. The strongest signals come from physical peril, thematic difficulty — these are the dimensions parents should evaluate against their reader's tolerance.

Specific content flags noted by reviewers: Mild Peril, Fantasy Violence.

Thematically, Case closed explores mystery, detective, adventure, friendship, and coming of age — these threads give the book room to mean different things to different readers.

Good fit for

  • Children in the Ages 9-12 range — the maturity and attention span match the story's pacing.
  • Kids drawn to stories about mystery, detective, adventure.

Maybe not for

  • ! Readers who get easily upset by emotional or moderately dark scenes — the conflict here is real, not just background flavor.
  • ! Children who are sensitive to violence, even when handled at age-appropriate levels.

For Parents

Content Intensity

9MP — Moderate — Physical
Emotional
Light
Physical
Moderate
Social
Light
Thematic
Moderate

Real stakes and emotional weight. May include sustained danger, loss, or bullying.

Content Flags

Mild Peril Fantasy Violence
Data confidence: standard

Was our "Moderate" content intensity rating accurate for this book?

Reading Insights

Hook Factor

3/10

A steady, thoughtful read that rewards patient readers.

Discussion Potential

3/10

A lighter read — great for independent enjoyment.

Book DNA

Multi-dimensional content fingerprint

Vocabulary Level
4
Emotional Weight
6
Theme Richness
7
World Scope
1
Data Confidence
7

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Details

Book Length

192 pages
ISBN
9781421565095
Pages
192
Publisher
VIZ Media LLC
Published
2015
Type
Fiction

Genres

Subjects

DetectivesGraphic NovelsHigh School StudentsMystery and Detective StoriesComics & Graphic Novels, Manga, Crime & Mystery