This book was advertised as the most complete account of Reagan's notorious scandal, and I can agree with this although I've not read the other accounts. Malcolm Byrne, the author, had all the material, records, diaries, personal notes that have been released through the FOIA. Byrne is a director at the National Security Archive, based in Georgetown, which relentlessly pushes our government to release records to the public.
The book is quite detailed and you can skip sections, but don't skip too many, for it is a treasure trove of stories, vignettes, and amazing concoctions created by the likes of Ollie North, CIA Director Casey, Richard Secord, McFarland, the CIA operatives, Israeli players, and Iranian intermediaries. If you were paying attention during the late 80's and early 90's, then your memory will be refreshed and the story completed. If this is completely new for you, be prepared to read what will be an amazing, but unsettling, story of how a President with his National Security Council populated with passionate ideologies can circumvent the law, justify their ethics and almost any behavior to achieve their ends. But then, it was Bush Sr. (himself fully involved) who took the wind out of the special prosecutor's sails by pardoning key players in the 11th hour of his presidency.
Regardless of the pardon, the behaviors are all there, fully documented, often in their own hand with notes and diaries, and in the hearings even admitted! Remember it was Ollie North and his secretary Fawn Hall who said openly under oath that it was their duty to shred the records because they could be used to incriminate the President.
What will be insightful are the author's linkage of personalities like Cheney to later events, and the evolution of the power of the National Security Council which competes with the State Dept to administer US foreign policy. There is a thread that began back in Nixon's day (remember Henry Kissinger?) that can be traced to Bush Sr, and the GW Bush administrations especially, but I suspect with more study one can fairly associate the Democratic administrations use of the NSC as a powerful executive arm that can rival or trump the power of Congress.