- I Found a Poo
- I Have A Hunch
- I Ladri di Regali
- I segreti di Acquamorta. Delitto al lago
- I So Don't Do Famous
- I So Don't Do Mysteries
- I So Don't Do Spooky
- I Think My Dad Is a Spy
- I'm Not Who You Think I Am
- Ibrahim Khan and the Mystery of the Roaring Lion
- Ice Claw
- Iced!
- Ich – einfach tierisch
- Identity Revealed
- Identity Theft
- If I Ran for President
- If I Were President
- If You Find This
- If You're Reading This, It's Too Late
- Illegal
- Im Bann des Flamenco
- Im Bann des Flamenco
- Im Bann des Tarots
- Im Tal der Buchstabennudeln
- Imagine What Happens Next…
- Immortal
- Imperia Jobsworth is Missing
- In Schnüffeln eine 1
- In Search of the Black Rose
- In the Nick of Time
- In the Wolf's Lair
- In Too Deep
- Incanto - 13. La leggenda della clessidra
- Indiana Bones
- Innocent!
- Insel der Piraten
- Inspector Flytrap in The Goat Who Chewed Too Much (Book #3)
- Inspector Flytrap in The President's Mane Is Missing (Book #2)
- Inspector Hiccups
- Inspector Hiccups - The search for Mae Louise Squirrel
- Inspector Josephine Black and the Case of the Missing Mona Lisa
- Inspector Penguin Investigates
- Intent: In A Coma
- Into the Abyss
- Into the Dark
- Into the No-Zone
- Intrigue at the Grand Opera
- Intruder
- Invasion of the Scorp-lions
- InvestiGators
- InvestiGators: Ants in Our P.A.N.T.S.
- Is Anybody There?
- Island Bound
- Island of the Blue Dolphins
- Island of Thieves
- It's a Mystery, Pig Face!
- It's No Joke!
- It's Valentine's Day, Chloe Zoe!
- It’s Just a Plant
- It’s Murder at St. Basket’s
- Ivy Aberdeen's Letter to the World