#WinniethePooh and #SherlockHolmes are free (in the public domains).
Thanks for ChatGPT, I give you 50 new titles:
"The Case of the Missing Honey Pot"
"The Mystery of the Disappearing Picnic Basket"
"The Adventure of the Lost Ball"
"The Search for Christopher Robin"
"The Puzzling Case of the Stolen Umbrella"
"The Baffling Theft of the Pooh Stick"
"The Hunt for the Missing Toy Sailboat"
"The Trail of the Missing Kite"
"The Enigma of the Disappearing Red Balloon"