A visit from Gram and Gramp Hollister in the Hollister home at Shoreham opens up the opportunity for the five children to go to Canada with their grandparents to see the Mardi Gras and Winter Carnival in Quebec. That, however, is not the only purpose of their trip. Mr. Hollister tells the children that a Christmas gift he had ordered for them has taken overlong in reaching Shoreham and, although he had wanted to keep it a secret, he is now worried about the delay. The gift was a cariole, a French Canadian sleigh, and was to be made by a master sleigh maker in Quebec. He commissions the children to try and solve the mystery of the missing sleigh.