"There are some paths woven so deeply into the fabric of the world, Merlin, that nothing can be done to change them."
— Merlin Series 5, Episode 11 "The Drawing of the Dark"
Merlin (or The Adventures of Merlin), the BBC television series that began as the somewhat slapstick story of the untold early years of Merlin and King Arthur as young men, but which eventually came to encompass the entire span of the Arthurian legends, grinds inexorably toward its conclusion with its fifth and final season (or "series," as per UK TV parlance). There will be spoilers in this post, but, honestly, the biggest spoiler for the end of Merlin may be that nothing all that surprising happens. Rather than put a new twist on the final chapter, as the show had with other parts of the legend, the writers this time largely hold fast to the traditional story as most people know it. Mordred joins the cast as the last major piece to be assembled toward setting the stage for the Battle of Camlann, which forms the climax of the story during the two-part finale.
Mordred's arrival (or return, rather—he appeared as a child (different actor) way back in Series 2) and his quick addition as a member of the Knights of Camelot don't really set anything into motion. His betrayal comes rather abruptly just before the final two-parter, and he's barely relevant during the major mid-season arc. Still, Welsh actor Alexander Vlahos's performance as Mordred is the high point of the season. This version of the young knight (also secretly a warlock, making him a natural enemy of Camelot, where magic is still outlawed) seems to genuinely mean well and tries hard to prove himself however he has to against judgment from every side. He's proud to be a knight, and, in some ways, he is the sincerest believer in Arthur, which makes it all the more painful when the king lets him down and sentences Mordred's druid lover to death. As Mordred struggles to maintain his knightly composure while tearfully pleading to Arthur on her behalf, Merlin delivers once more one of its signature dramatic turns, when this typically lightweight, unassuming, even silly show suddenly becomes very weighty and very powerful. When Arthur shuts him down, not since "I Love Lisa" has it been possible to so pinpoint the moment of a character's heart breaking on TV, as cruel fate crushingly sweeps aside at once all he has hoped for, all he has believed in, and all he has ever loved. It's an outstanding moment and an outstanding performance.
The pity is that, as with Morgana, the story builds so deliberately toward that masterful moment when this character, once as innocent as any of us begins, at last becomes the villain we know from legend, only to leave us with an antagonist that is subsequently incredibly poorly developed and extremely one-dimensional. This is the third season of evil Morgana, and, with not even a glimmer left of her originally heroic character, her stark villainy now frankly defies comprehension. The one thing that Smallville, which inspired this show's conception, may have handled better than Merlin was the friend-turned-nemesis angle. Before Lex Luthor finally turned full dark side on that show, there was a much longer period during which the darker aspects of his self grappled against his conscience, and, although he would (rightly) suspect Clark Kent of not being an honest friend to him, still Lex would, more often than not, stand by Clark, whose friendship he genuinely valued.
It probably helped in Smallville's case that Lex was a morally ambiguous character to begin with, rather than being a clear good guy, as Morgana was at the beginning of Merlin. But the creators of Merlin must have known all along where they intended the character to end up; they clearly knew that it was all going to lead into the Arthurian legends we know. The liberty they took was in where they had Morgana begin. Sadly, her arc across five seasons of Merlin mostly just suggests that the writers never knew how to make that transition. There is really no way to reconcile the person Morgana is at the beginning of the story with the person she eventually becomes. Either she should have been more morally ambiguous in the beginning, or perhaps the writers should have been daring enough to take more liberties with the ending. Instead, it just feels like they wanted Morgana to start out heroic, then they made her evil for no better reason than "because that's what's supposed to happen," and, after it happened at the end of the third season, they kind of stopped thinking about it altogether and kept her simply as this one-dimensional antagonist. These turns are all the more depressing on Merlin because the prophetic "that's what's supposed to happen" angle is actually written into the show's mythology. Like the viewers, Merlin even knows that Morgana and Mordred are going to turn on Camelot well before they do. That he is consistently powerless to do anything about it makes this eventually kind of a dreadfully fatalistic show.
The finale aside, this last season includes among the show's least memorable standalone(-ish) episodes, which all tend to be on the more serious side. The mid-season arc, centering on Guinevere being brainwashed by Morgana to spy on Camelot, actually provides some of the season's more humorous moments (when Merlin and Arthur grow wise to the plot and have to figure out how to hinder Guinevere without either harming her or tipping her off), but it goes on for too long without ever really progressing anything. Previous seasons of Merlin had largely managed to avoid feeling labored, despite the fatalism, but the Guinevere story is too predictable, and if you actually remove it from the season altogether, you realize it has almost no effect on the continuity of the story.
Despite my disappointments with Merlin's fifth season, the ending mostly works, and the final images are quite poignant. Honestly, even if it's not altogether satisfying, I don't know how they could have handled the end to such a story any better. All told, Merlin was still, for five seasons, a surprisingly diverting program, and quite often something more.