Though little is known about Amazon's new Lord of the Rings TV series, it seems a villain even more formidable than Sauron could appear. Throughout the Lord of the Rings trilogy, Sauron is the overarching threat Frodo and his Fellowship are quested to vanquish. Defeated by Isildur at the end of the Second Age, Sauron eventually recovers thousands of years later during the era of The Hobbit, and begins seeking the One Ring that'll restore his power fully. Thanks to the heroics of Frodo and many others, this eventuality never comes to pass, and the full force of Sauron's might is never felt during the Third Age. All species breathe a collective sigh of relief.
Since the entire Lord of the Rings story is about preventing Sauron's return, it's difficult a fathom a greater power, but in ages long past, Sauron was merely the follower of a bigger, better Dark Lord - Melkor. While Sauron is a Maia, Melkor was a Vala (comparative in stature to angels and archangels), which meant Melkor was very much dominant in the hierarchy, and though Sauron took over his master's role menacing Middle-earth, he remained a worshiper of Melkor (who would later be renamed Morgoth after his corruption).
Morgoth was only defeated by the combined might of his fellow Valar, who rode forth in a glorious host to vanquish their very own Lucifer. This battle occurred upon the conclusion of the First Age and Morgoth hasn't been spotted since, so few fans were anticipating Lord of the Rings' biggest villain would feature in Amazon's Lord of the Rings TV series, which had confirmed Tolkien's Second Age as its setting. The very first image taken from the show, however, strongly suggests otherwise. The picture reveals the Two Trees of Valinor - Telperion and Laurelin. These divine creations were revered for their light and beauty, and existed prior to Tolkien's First Age before being destroyed by - you guessed it - Melkor.
That Amazon's Lord of the Rings series includes the Two Trees of Valinor (and has shown them in its maiden promo image, no less) heavily implies that viewers will witness how these trees were poisoned. This surely means a Melkor appearance is inevitable, perhaps alongside his spider-like partner-in-crime, Ungoliant (a distant ancestor of Lord of the Rings' own arachnid, Shelob). Even if Amazon's Valinor scenes only serve as part of a flashback sequence galloping through the biggest events in Middle-earth history, Melkor is almost certain to feature - an unexpected treat few would've hoped for when Amazon's "Second Age" project was first announced.
Any appearance from Melkor/Morgoth in a live-action setting is a huge deal. For a start, he's responsible for triggering the darkness still present during the Lord of the Rings trilogy. Not only does Melkor indoctrinate and corrupt Sauron, but he also turns a perfect and idyllic Middle-earth into the world of monsters and shadow seen in Lord of the Rings. Whether it be the Balrog, Shelob, Sauron, or even the feud between elves and dwarves, virtually every bad thing in Middle-earth can be directly or indirectly traced back to Melkor, cementing the villain as one of Tolkien's most pivotal creations. However brief his appearance on Amazon Prime Video might be, audiences should gain a much deeper understanding of the Lord of the Rings tapestry after seeing Melkor in action.
Melkor's live-action debut also marks a steep shift in power-scaling compared to The Lord of the Rings. The three most powerful characters in the trilogy are Sauron (despite being without form), Gandalf and Galadriel - and Melkor's power greatly overshadows all three. Should the original Dark Lord drop by when Amazon's TV series premieres in September 2022, fans should see a very stark, and very exciting, escalation of magical prowess in the live-action Lord of the Rings realm.