In The Gang of Sjako are the brothers of Sako Jacco (12) and Vin (8) and their friends Sam (12), Marco (13) and Mo (12) central. They proved to be descendants of the 18th century Amsterdam Sako thief and his gang members. Shako in his time a kind of Robin Hood. He has a wealth stolen from a mysterious group, the Regents, and this treasure hidden in a secret place.
A mysterious phantom of Regents has been commissioned to test Jacco, Vin and their friends the new Sako gang could form.