This book is 100% analysis and comments, it contains no works. For that you need another book as a reference as you read this present book. Of all the Shakespeare analysis books, this is book by Asimov is one of the best books available, and very reader friendly and entertaining.
Here is the analogy. Your hobby is Shakespeare and you have just won the lottery. You have decided to quit your day job, shun the world, sit down, and go over every one of Shakespeare's plays, dissect each scene in chronological order, find out where the characters' names came from, how the plot relates to original source stories such as the myth of King Lear, etc. You research such facts - as they might be available - on whether Shakespeare really did invent the plot of the Tempest all on his own, or as Asimov thinks perhaps it was based on a boat crash in Bermuda. You would go on and on... looking at all the interesting details and side notes plus you would find some maps and drawings. Then - possibly five years later - you would take all the notes, hire Tom Clancy or some other well known modern novel writer and together you would write this easy to read 750 page reference book. Perhaps you could sell a few copies.
That would be your labour of love, and that it exactly what we have here. Asimov has taken the time to methodically go through all the major works, divide them into three groups, i.e.: Roman-Greek and ancient tales, Italian-Mediterranean more modern tales, and finally the English-Europe stories starting with King Lear. He does not need a writer's help - he brings that to the table. Each play is treated in a short chapter and gets about 20 to 40 pages of analysis, general source comments, and specific comments on a few key lines. He has all the skills needed to keep our attention, make it simple, give us lots of background trivia plus the key guidance, and make it all entertaining.
I think most would agree that the best book on Shakespeare is the 3500 page monster: The Norton Shakespeare. But the present book is friendlier and at 750 pages easier to read. So this is an excellent reference where one can get a very fast and painless summary of all the works with many interesting details on lines and characters scene by scene without feeling lost or overwhelmed - as sometimes happens with Norton - a book that one can barely lift. Asimov's book is a must buy for most Shakespeare lovers even if you own other books. Simply put this book is a joy to read, an integral part of any Shakespeare library or fine on its own. Asimov spent all that time and made a serious effort, and now we can enjoy it for a few dollars.