With a title derived from an elegy written by Percy Bysshe Shelley (Adonas: An Elegy on the Death of John Keats), "Adonais" takes an interesting premise and uses it as a tone poem that doesn't really develop a story.
When this episode first aired in 1967, it was ahead of its time. One year later the book "Chariots of the Gods?" was published and the same idea (that aliens visited the ancient civilizations of earth) became a pop cultural phenomenon. Here, however, the idea goes mostly unexplored and just serves to set the stage for another all-powerful being to mess around with the Enterprise before Kirk figures out "his bag of tricks". It's a plot that has grown stale by this point, though it would continue to pop up, even in the Animated Series, and the feature films.
Shakespearean thespian Michael Forest, guest starring as Apollo, uses a mid-Atlantic accent (which Patrick Stewart would later make famous) to great effect, and he gives his character a strong sense of pathos. There's a bittersweet sadness in the idea of mankind leaving a god behind like a son or daughter becoming a teen and no longer idolizing a parent. But Apollo simply has too little to do other than mope. The plot can be summed up as Apollo asking for worship, Kirk refusing, Apollo becoming angry, and having it all repeat over and over until the end, all on the same "planet" stage used in "Amok Time" (redressed to look like ancient Greece). Reminiscent of Madlyn Rhue's part in "Space Seed", Leslie Parrish plays a female officer smitten with Apollo, ultimately having to decide whether to please him or Captain Kirk. (She's actually decent in the part, though the sexist idea that she needs to leave Starfleet when she gets married doesn't do much establish her character). Meanwhile, Spock gets a short B story on the ship, attempting to (quite literally) break free of Apollo's grip. It all gives us some memorable bits, from the visual of a giant hand to Apollo's final soliloquy, and it's set to a beautiful score by Fred Steiner; but with no story, the pieces just don't add up to a meaningful whole.
Remastered Edition: With the original version of this episode having to cheat its way around some difficult visual effects, it leaves quite a bit of room for improvement. CBS Digital is happy to oblige. To give credit where it's due, the signature effect for the episode is a giant hand grabbing hold of the Enterprise, and it's always been rather well done. (The CBS team redoes it but keeps the concept the same). Unfortunately, back in the 60s the original effects team couldn't add anything else to this shot, because compositing three images together was just too difficult. As such, the original footage can't show the ship, the hand, and the planet in the same shot, with the end result being that the planet disappears for most of the (original) episode. Also, late in the episode when the Enterprise fires its phasers, the hand is inexplicably gone. Fortunately, digital technology allows for more freedom, and the new effects fixes these issues by including an Earth-like globe throughout and having the Enterprise punch through the hand with phasers just as the dialogue indicates (with the script likely written before the original effects team figured out it wasn't possible for them to do). The CBS team also corrects the color of the phasers and touches up a shot of a temple being leveled. On the other hand (pardon the pun), there's a special effect that proves too much for CBS Digital to replace. Apollo's head appears on the viewscreen amidst a background of stars, and to matte the guy into a new star field would require some intense, time consuming work. With the original effect working just fine, they wisely leave it alone, giving us a rare shot of the stars in a remastered version that hasn't been redone. (They also leave an obvious mistake alone. At the end, as Apollo gives his final speech, there's a tree behind his head. Yet supposedly he's a giant, with no tree nearly as tall as him. It's the classic case of not seeing the Forest for the trees).
Special Bonus Review
Pilgrim of Eternity: 6.5
Apollo returns to wreak havoc on Kirk and the Enterprise.
Where did this one come from, you ask? Well in 2013, Vic Mignogna spearheaded an effort to make new episodes of the original series for fans to enjoy. Funding the first episode himself, Mignogna brings back Michael Forest to reprise Apollo in "Pilgrim of Eternity", an episode that premiered at Phoenix Comicon. While the series features new actors playing the old parts (including Mignogna himself as Captain Kirk), it meticulously recreates the original sets, lighting, camera angles, tone, and structure and reuses many old elements, such as sound effects and music. For obvious copyright reasons, Mignogna is unable to profit this work, but its real purpose is simply to entertain fans of the original series, and as such, all the finished episodes are available online for free viewing.
For "Pilgrim", Apollo is back, and this time he spends the episode on board the Enterprise. Forest steps back into the Greek God's shoes without missing a beat, and with this authenticity and all the familiar sets around him, the episode makes it easy to accept you really are back in the Original Series. As the script moves along, it picks up threads from "Who Mourns for Adonais" and develops them in a way "Who Mourns" never does, even allowing Forest to sing in one of the episode's most poignant moments. Meanwhile, the visual effects hold up their end of the bargain, being nearly on par with the remastered versions of the original series.
Unfortunately, the episode is not without its flaws. Beyond Mignogna, the actors aren't fabulous, ranging from "ugh" to adequate. (The cast includes Chris Doohan, son of James Doohan, as Scotty, Mythbuster's Grant Imahara as Sulu, and Marina Sirtis as the voice of the ship's computer). In particular, Scotty spends the episode almost comically angry, and Imahara is tries too hard to summon his inner George Takei, creating a parody. More than that, however, the series misses Nimoy and Kelley, with no amount of money or effort able to make up for the loss. With most fan presentations, it's not so noticeable because there are too many other sins. Here, however, everything is present but these guys, and it's hard not to bemoan the fact that we can't do a slingshot around the sun, pick up the original actors from 1969, and drop them in these episodes.
The script itself is not without issues, too. While strong early, begins to falter in the second half. The point of the story is to build a moral dilemma, but in the process the danger and tension dissipate. Of course, the premise itself is built on a weak (if memorable) episode, so it only has so much steam in it.
In the end, however, the episode is probably just as good as its prequel and better than quite a few Original Series episodes. For an old fan who has watched the original 79 a hundred times, it can be quite a trip to watch a new episode of the original Trek once again!