Secrets of the Russian court. Rurikovich and Romanovs

The history of Russia of the era "from the Rurikovich - to the Romanovs", perhaps more than all others, is rich in riddles, unsolved secrets, and sometimes unsuccessful crimes that are not inferior to the current detectives.
Does the murder of Tsarevich Demetrius lies on the conscience of Tsar Boris and how many False Dimitians actually gave rise to a vague time?
Was Ivan the Terrible predecessor of Peter I, a monarch-reformer, or just a bloody, but weak-willed tyrant?
How did you manage to ascend to the throne and edit the weak woman " - Princess Sofya, who was not prepared for public affairs?
And finally, as Peter the Great raised his “miserable semblance” and a traitor from the only son, Tsarevich Alexei, and was that traitor actually?
The answers to these questions should not be sought in the modern works of "alternative historians" and journalists - they will be given to you by the book of Nikolai Kostomarov, a classic of Russian historical science