Brad Meltzer is a best-selling author in both fiction and non-fiction. I love reading his books and love having him on the show. His latest is a non-fiction book entitled "The Nazi Conspiracy" about a Nazi plan to assassinate Roosevelt, Stalin, and Churchill during their first all-in-one-place meeting in Tehran in late 1943. Tehran Conference - Wikipedia
The details are fascinating as is the fact that it's not 100% certain that the plan even existed though the weight of the evidence suggests that it did.