When the Boxcar Children visit a neighbor's house, a mysterious old wedding photo and a riddle lead them on a "spy game" devised long ago by the original owner of the house. When the children hunt for clues they discover amazing things, like a stone path whose pieces fit together into a jigsaw puzzle! But soon the children begin to suspect that there's a mystery inside the mystery. They read about a similar puzzle in one of their new Detective Club...

Cousin Alice is running for mayor in her town, and the Aldens are helping with her campaign! But, Alice's campaign posters are torn down and painted over, and the same thing happens to her opponent! Then posters for a third candidate appear around town, but nobody has ever seen him in person. Will the town elect a mystery man for mayor? The Aldens are on the case!

The entire town is excited about the summer music festival-especially the Aldens, who have been asked to help with the show. The largest attraction this year will be the popular Greenfield Four. A big-time music producer is going to be in the crowd to catch the show, and Greenfield residents hope their favorite local group will be famous soon. The day before the show, The Greenfield Four arrive at the rehearsal hall to find all of their instruments...

The Aldens are preparing for a yard sale when they find an old wooden mask in the trash behind a neighbor's house. Violet notices that the mask looks like a Native American mask that she had read about. When the children go to the library to learn more about the mask, they discover that they have found an old Native American mask from the Hopi tribe. When the children learn there will be an Intertribal Pow-Wow at the park over the weekend, they plan...

The Aldens are visiting Grandfather's friend, Amy, at the Ogopogo Retreat in Canada. Amy rents cabins to tourists who hope to see the mysterious underwater creature, the Ogopogo, swimming in the lake. Henry, Jesse, Violet, and Benny can't wait to try to spot the Ogopogo from their cabin. Amy tells the children about a riddle that an old friend left for her in one of the cabins that could lead to a small treasure. The children need to find the treasure,...

One day in the park, the Aldens' dog, Watch, comes across a mysterious box with a note inside. "Congratulations!" the note says. "You've found it!" The box is part of a fun new treasure-hunting game, and soon Henry, Jessie, Violet, and Benny are looking all over town for cleverly hidden boxes. But, they're not the only ones on the trail for clues! When several of the treasure boxes go missing, the game is ruined for everyone. Who would steal the boxes,...

A hip new doughnut shop known for its bizarre recipes is opening up in Greenfield. At first, the owners of the other doughnut shop in town, Delilah's, aren't worried. But, when the new shop starts making doughnuts that look just like some of Delilah's greatest hits, the Boxcar Children must figure out if it's just a coincidence or if someone, from the new shop is stealing Delilah's recipes.

It's a delicious new mystery with the Boxcar Children as they help catch a cupcake thief! Mama Tova's shop in Greenfield is so famous that every day, people line up around the block to buy her cupcakes. But when someone breaks into her kitchen, it's clear that her secret recipe is in danger. The Aldens follow the suspects to a bake-off where they must find the culprit using their mystery-solving skills-and their taste buds, too!

Grandfather's friend, Mr. Yee, has broken his arm and can't tend to his beloved vegetable plot in the community garden. The Alden children gladly offer their services to help him with his prize-winning veggies. But, they soon learn something mysterious is afoot at the community garden. Vegetables go missing, and it appears someone is intentionally vandalizing the garden plots. Luckily, for the local community gardeners, the Boxcar Children are on...

The Aldens are excited to meet their favorite celebrity-Walter the Cat, who makes the funniest videos on the Internet! And, when this celebrity cat inherits a million dollars from his owner, he becomes even more famous! But, someone seems to be angry about the will and is stealing things from Walter's house. Is this cat too famous for his own good?