In the latest musical family film De Grote Sinterklaas film: Gespuis in the Toy Vault, Hugo Hogepief is given the important task of looking after Sinterklaas' key ring. This ring gives access to the safe in which all the presents for Christmas Eve are stored. But when he accidentally falls, Hugo no longer knows who or where he is.

When Mammie and Stan are freed from jail the two once again set their sights on eliminating the Black Petes and Saint Nicholas.

Sinterklaas is back in the country, so it's high time for the annual "Great Gingerbread Baking Competition." Bakers from all over the country are vying for the title: Master Baker of the Year. Marco Marsepein is also determined to win, as he succeeds every year. His dearest grandmother's secret recipe has never let him down. But... this year, Bartus Bakker and his father are also vying for that coveted first place. The evil baking duo cunningly steals Marco's secret recipe and ruins his gingerbread dough. When Bartus Bakker wins the baking competition, Marco is utterly devastated. He decides to leave Sinterklaas's castle and return to his native Italy once and for all. But what would a great Sinterklaas celebration be without Marco Marsepein and his gingerbread?

Sinterklaas plans to celebrate his birthday lavishly. This year, he's coming to the Netherlands for the hundredth time, and that's reason for a big party. He wants every child in the Netherlands to receive an extra present this year. At the same time, the Pieten (Black Petes) plan to surprise Sinterklaas with a big party, culminating in a special performance by one of the Netherlands' most famous artists. Robbie Reuzel, whose birthday is also on December 5th, hears about Sinterklaas's grand plans and becomes furious. After all, it's not the first time his birthday has been ruined by Pakjesavond (Santa's Eve). He devises a plan to outwit Sinterklaas, taking advantage of his witty neighbor, among other things. Will Robbie Reuzel succeed in thwarting Pakjesavond, or will the Pieten smell a rat and save the Sinterklaas celebration?

Every year, Sinterklaas and the Pieten eagerly look forward to their big journey to the Netherlands. In the castle, preparations are in full swing. The two new "Pieten-in-Training" (PIO's for short) are soaking up everything like sponges, eager to prove themselves. Everything seems to be going according to plan until disaster strikes. Jean-Claude takes a nasty tumble down the stairs and ends up bandaged. To make matters worse, his Aunt Poets suddenly shows up at the castle. She insists on taking over the housekeeping.