As Justin Taylor wrote, "Richard Wurmbrand (1909–2001), whose many years of imprisonment in Romania for the gospel included three years in solitary confinement, went on to write Tortured for Christ and to found Voice of the Martyrs."
Taylor posted a 9 minute video which is well worth seeing. I just visited YouTube and discovered a number of additional videos of Wurmbrand speaking. I plan to watch many more.
I might add that I had the privilege of hearing Richard Wurmbrand speak in person in London in the late 60's. My impression was the same as those who described the first Christian martyr, Stephen: “And gazing at him, all who sat in the council saw that his face was like the face of an angel.” – Acts 6:15