When the god of thunder's hammer goes missing, Magnus Chase and his friends are tasked with retrieving it before an onslaught of giants attacks the mortal world.

Biff and Buff are two very small dogs who are happy to travel in Mr. Pocket's pockets, until Biff falls through a hole one day.

When she cannot find her favorite stuffed toy, a young girl asks her mother, father, and older sister for help.

While looking for bottle caps on the beach, a young boy stumbles upon a lost "thing," and tries to find out who it belongs to.

One mitten can do many things, but when the second mitten is found, it is time to go outside and have fun.

Eight-year old Alex is determined to keep the toy mouse he finds tied to a balloon, even after posters appear asking for its return, but when his dog Patch disappears, Alex discovers what it is like to lose something you love more than anything.

When Horrible Harry's pet cat, Googer, sneaks a ride and gets into the school building, third-graders Harry and Doug have to catch him before anyone else does, which means going into some forbidden places.

While traveling with her family to Holland to visit her grandparents, Trixie once again loses her beloved Knuffle Bunny.

Mia is ready for Christmas except for a tree but on her way home with one, she stops to help an old man who has fallen, leaving the tree behind, and soon it is too late to find her tree, in a story about the real gifts of Christmas.

After awakening to find that her pet ferret is now pet feet, a young girl discovers that the letter "R" has disappeared and its absence is causing chaos throughout her town.