The festive arrival of Sinterklaas is overshadowed by a huge problem: due to a large shortage of staff, the tradition threatens to disappear once and for all. Sinterklaas is desperate: where can he find new, good staff on such short notice? The youngest member of staff suggests they organize an audition in which everybody can show off their skills in order to become a member of staff; a so-called 'Piet'. Sem writes a letter to register for this audition immediately. If he can become a tough, strong 'Piet', his bullies will never harass him again. But what nobody knows is that Huibert Jan and his "Mammie" are trying to sabotage the audition with an evil scheme. Will Sem, Patty Pepernoot and 'Piet' Bennie successfully save the audition or is this the end of the festive and beloved Sinterklaas tradition?