[2][3] His criminal history included the robbery of over 70 Pewex stores of scarce luxury goods[2] and stealing over 100 FSO Polonez cars.

[6] At the age of 20, after battering a police officer in a pub near the town of Żyrardów,[4] Najmrodzki was imprisoned in Gliwice for one and half years without the right to a suspended sentence.

A few hours into the journey, the two police officers who were guarding the prisoners agreed to remove Najmrodzki's handcuffs and drank beer with him.

[6] After the guards had fallen asleep, Najmrodzki jumped out of a window[4] and returned to Gliwice, where he hid at his friend's house and forced his wife to remain silent when questioned by the authorities.

They planned for Najmrodzki to distract police patrols, allowing convoys of lorries to smuggle clothing (mostly jeans) into Poland.

Najmrodzki created a distraction by recklessly driving a Fiat 131 Mirafiori, thus allowing the lorries to pass unexamined.

[6] After some time, Najmrodzki organized a criminal group which he used to rob over 70 Pewex stores, which sold luxury goods and scarce products[2] but were not equipped with security alarms.

In the evenings, he attended parties in the best clubs, always wearing expensive suits with a gold watch and a chain around his neck.

By this time, he had started using the pseudonym Szaszłyk, a Polish word meaning shashlik, which was his favorite dish, and due to a speech disorder, pronounced by him in a way that was considered amusing by others.

While under arrest, Najmrodzki managed to smuggle out a letter containing the blueprints of the building, including the room in which prisoners were awaiting trial.

While doing so, Najmrodzki had a rule that stolen vehicles should be sold only to people who "profit from the poor and weak", and focused on rich clients.

[3] Efforts to stop the gang included the formation of a Civilian's Militia special group under the code name "Polonez".

Najmrodzki managed to escape from the authorities several times, but eventually, on 3 March 1983, he was caught after a car chase outside Warsaw.

The Civilians' Militia ordered an increase in the intensity of the search for Najmrodzki, making him a more wanted person than the members of the Solidarity movement.

[2] On 19 November 1989 in Kraków, while drunk with 0.21 BAC of alcohol in his blood, Najmrodzki crashed a Polski Fiat 132p he had stolen three days earlier into a street lamp.

While recklessly driving a stolen BMW car with a fake vehicle registration plate, he skidded and drove into a LIAZ lorry on the other side of the road.

[14] In 2018, Gliwice Town Thetre put on a play entitled Najmrodzki, czyli dawno temu w Gliwicach, based on his life.