I'm not exactly sure what the point of this book was aside from trying to cash in on the usual conspiracy theories surrounding Stalin's purported invasion plans when it came to Germany during the Second World War. In the usual style of those who enter into this type of conspiracy theory laden discussion, we begin with the Revolutionary/Civil War period and proceed to the eventual German invasion of the Soviet Union in 1941.
A monograph that tries to cover that much territory in about 300-400 pages means there will be more missing than included, especially considering the numerous topics that need to be touched on, discussed, contextualized, etc. The basic idea for this author is that the Communist Party of the Soviet Union always aimed to export Revolution. Was Stalin going to invade Germany? Maybe in 1943, but it's still all speculation and conjecture according to the author. That, in essence, is the entire book. Nothing new, nothing original.
What are the strengths? The author uses some good documentation from the archives and other primary sources. That's it for the strengths.
What are the weaknesses? Everything else. Those documents and primary sources need to be contextualized and they rarely are. The numerous volumes that exist in terms of research on dozens of topics that are covered here are rarely if ever referenced nor are large, block quotes that are often introduced adequately contextualized.
Does this book develop a new central thesis/argument? No.
Is it worth your time/money if you're familiar with the history of the Soviet Union, WWII, or the Eastern Front? No, and if you're not familiar with those topics, then this isn't a good starting point for them.
I'm not at all sure who this book is for unless you're a fan of conspiracy theories and need some additional ammunition to reinforce what you already believe.