Amazon secured rights Tuesday to “The Lord of the Rings,” but what exactly did the streaming service get for (a reported) $250 million, which is possibly the richest deal in TV history and one expected to yield an extravagant new series and possible spinoff?

 You’d be surprised. Foremost, here’s what it doesn’t get: “The Lord of the Rings.” That classic, published in 1954, has already been made into a classic movie trilogy, and there are no plans to improve upon that which cannot be improved. ”The Hobbit” (1937) has also been done (and done and done). Rule that out, too.

So? Here’s essentially all that Amazon has said: “Set in Middle Earth, the television adaptation will explore new storylines preceding J.R.R. Tolkien’s ‘The Fellowship of the Ring.’ The deal includes a potential additional spinoff series.”

With “LOTR” and “The Hobbit” out of the picture, what does that leave Amazon? Again, you may be surprised.

Over his long professional life, from before the First World War to his death in 1973, Tolkien created a vast mythic cosmos known as the “legendarium.” The legendarium comprised the history, cosmology, mythology and even philology of Middle Earth. “LOTR” was part of the legendarium, but much, much more was as well, some of it covering the vast span of history before the events of “LOTR.” Tolkien wrote books, stories, poems, drafts and essays which comprised the legendarium; a well-known one (still awaiting adaptation) is “The Adventures of Tom Bombadil,” published in ‘62.

 Tolkien’s son, Christopher (who closed the deal Monday and is 92), has collated and edited much of the work that fills the legendarium. The most famous, and perhaps most densely packed, volume relating to it is “The Silmarillion.” Though not exactly a “story,” “The Silmarillion” -- the “Silmarils,” like those famed rings, were jewels crafted before the so-called “First Age” -- offers a particularly detailed road map to everything, including the history of the universe (Eä) in which “LOTR” would later be set.

Then there is “Beren and Lúthien,” edited by Tolkien and published this past June. “Beren and Lúthien” may well be the basis for the Amazon series. Set thousands of years before events of “LOTR,” it’s a love story about a mortal man (Beren) and immortal Elven woman (Lúthien). It’s the story that anticipates the famous one of Aragorn and Arwen in “LOTR,” but there’s a key difference here. Her father demands they complete an impossible task before they marry. Together they must steal a “Silmaril” from Morgoth, predecessor to Sauron -- but an even bigger bad than Sauron, if that is possible.  

In this story, Lúthien is the superstar. Think Wonder Woman meets Elektra Natchios meets Buffy Summers. In their journey, there are lots of new villains to battle as well, including werewolves, vampires and more Balrogs -- one of the so-called servants of Morgoth, and which famously fell to its death in “LOTR” after a titanic battle with Gandalf.

 Amazon has lots to work with, and now the richest deal in TV history is about to become the most anticipated.