[2] He was the author of over 30 non-fiction books with the total circulation of 1.5 million copies, and the recipient of numerous national awards and honours.

Kąkolewski published his first novella at the age of 48, after nearly three decades of often controversial (from the communist standpoint), but highly popular non-fiction works about events in Poland's postwar history.

[1] He interviewed former Nazi criminals living safely in Western Germany, e.g. Hans Fleischhacker, Heinz Reinefarth, subsequently described in his book Co u pana słychać?

His criminal novel based on authentic MO police records Zbrodniarz, który ukradł zbrodnię was filmed in 1969,[3] as one of the best Polish movies of the time, starring Zygmunt Hübner and Barbara Brylska.

Kąkolewski wrote an entire book about the seminal postwar novel Ashes and Diamonds written by Jerzy Andrzejewski and filmed by Andrzej Wajda.