You can read a recent news article about Reinhard Heydrich at https://sofrep.com/76321/reinhard-heydrich-hunting-devil/
The following quote is from the news article:
Apart from Hitler, perhaps no one typified the evil of Nazism more so than Reinhard Heydrich. Cold, calculating, arrogant and brutal, he is a figure whose hands-on approach to dealing with perceived enemies of Germany made him author of some of the worst crimes ever perpetrated by man.
Tall, slender with smooth blond hair and a somewhat high pitched voice, he joined the SS in the early 1930’s, and quickly rose through the ranks with cutthroat efficiency, running the SS intelligence service, the Sicherheitsdienst or SD. In this office, he helped orchestrate notable events which defined Hitler’s policies by purging suspected political rivals in what became known as The Night Of The Long Knives in 1934, and terrorizing Jews in the Crystal Night pogrom of 1938.
I am not a fan of Reinhard Heydrich, but he is an interesting person who has gotten a bad rap.