Kruimeltje witnesses a couple of crooks robbing local grocer Baas Wilkes. Nearly getting blamed for the crime himself, Kruimeltje sets a trap for the crooks and lead the police to them.
Despite his own troubles, Kruimeltje is determined to help others in need. Meeting a sad man with no wife or children, Kruimeltje introduces him to a desperate woman with a large family but no husband or money.
In her last moments, Mrs Koster tells Kruimeltje what little she knows of his parents and gives him a locket holding pictures of them. Back on the streets, Kruimeltje intervenes when he sees a dog being badly mistreated by its master.
Now homeless, Kruimeltje has to sleep on the streets in the snow, but is rescued by Baas Wilkes who takes him in for the night. The following day, an unscrupulous glazier offers to pay Kruimeltje for breaking windows.
Things are looking up for Kruimeltje as he starts working for Baas Wilkes in return for a place to stay. While looking for Moor, Kruimeltje and Keesie sneak into a theatre where a famous pianist is performing.
With Wilkes in hospital after a fire at his shop, the commissioner takes an interest in Kruimeltje's welfare and insists he not only goes to school, but also must stay at a boys' home run by cruel Father Keijzer.
Kruimeltje runs away from the boys' home and while visiting Wilkes in the hospital, he cheers up a sick girl, and gives her hope in her recovery. Meanwhile, Wilkes decides to go to America in search of Kruimeltje's father.
Wilkes makes Kruimeltje promise to return to the boys' home while he is in America. Although Kruimeltje is doing well at school and is popular at the hospital, Father Keijzer is determined to cause trouble for him.
Father Keijzer accuses Kruimeltje of theft and with Buikie's help, convinces the commissioner that Kruimeltje is guilty. Kruimeltje hides in his former home, Mrs Koster's house, but is nearly caught when the landlord returns there.
Kruimeltje is hit by Vera di Borboni's car and while he is recovering in her home she discovers and recognizes his locket. Wilkes returns from America having found Kruimeltje's father, and the whole family is reunited.