Just when you thought the Eastern Front couldn't get any more appalling

My current read is War of Annihilation: Combat and Genocide on the Eastern Front, 1941 by Geoffrey P. Megargee.

I am not very far in so it's been background so far but it will lay out how, contrary to popular perceptions, the Wehrmacht colluded with the SS to help carry out the Holocaust and just inflict heinous cruelty on civilian populations in general. Just when you thought the Eastern Front couldn't get any more appalling.

Here's Megargee giving a lecture on the subject.