The titled monster of the story is an awe inspiring giant who spends most of the time mired in the deep swamps of some distant moon. And that, isn't a bad analogy for the story either.
The Power of Kroll is one of those stories which features one of Doctor Who's less admirable qualities, starting a story off strongly in episode 1 but then fumbling around in episode 2. What makes this even more disappointing is that it is one of the last stories to be written by well-loved Who author, Robert Holmes, a man who gave us some brilliant adventures, many of which are still beloved today. Buried deep in the story we have been given, there is the potential for an even better story, one which could be about colonialism, capitalism, racism and religion which plays like a mixture between Avatar and a horror film. It was disappointing that after writing this story, Holmes left the series for five years after helping to establish Doctor Who's mythology and making it a television event which drew in many millions of viewers during the mid-1970s. The Power of Kroll does have its problems, but it feels more like a misfire rather than mediocrity. If things had gone a little differently, this story certainly had the potential to be the strongest story from the show's sixteenth series. It is a damn good job then, that when he did come back, he penned the brilliant Fifth Doctor swansong, The Caves of Androzani. But, despite this story's faults, it is certainly more consistently entertaining than the other stories of the series except for The Ribos Operation, also written by Robert Holmes.
As with all the stories in this series which focused on gathering all the segments of the Key to Time, the plot of the adventure is split into two. For this story there is a feud between colonists and the moon inhabitants, which have been cruelly called Swampies by the invaders. And just as the TARDIS lands, things get nasty, The Swampies have secretly brought guns from a gunrunner called Rohm-Dutt and the invader's, who live in a refinery in the middle of one of the swamps, has an unpleasant, racist leady called Thawn, who is ready to commit genocide. But literally underlining everything is the Godzilla-sized Kroll, a mutant space squid who has been lying dormant under the swamps for centuries while its legend has grown into a fully fledged, killer cult. As the story progresses, we discover that Kroll is the fifth segment of the Key as at some point in it's history, it had eaten it. Making it the central part of the plot, the Doctor and Romana are pitted against both the men at the refinery and The Swampies, as they try to collect the segment and return to the TARDIS.
However, there is something of a disconnect between the two storylines. On the one hand, the Doctor and Romana are in what really amounts to an Indiana Jones-type movie, quipping their way through the deathtraps that litter the moon. This storyline takes itself so unseriously that we literally see the Doctor singing himself out of one predicament. But that is also quite fun, what is bad about seeing Tom Baker stomping baddies by throwing some funny lines at them? The second plotline is more serious by nature, with Holme's particular cynicism about Human nature, bubbling not too far below the surface.
This proceeds to create quite a balancing act, one approach works better when it takes thing a little more lightly and the other when it is more serious. Unfortunately, neither carries the day and end up getting in the way of each other. This damages Holmes' attempt to tell a really serious story, which, if it had worked, would have made The Power of Kroll, something more than just a story about the Doctor and Romana trying to find the next segment, but turning it into a stab at telling a story about dealing with bigger issues as well.
The Power of Kroll is noteworthy however as it is the first story from this story to see the Key to Time playing a big role. Looking at the series with hindsight, it doesn't look like any thought was really given to how the stories would tie together beyond the fact that each one would have a piece of the key involved somewhere. Surely this was the entire point of having a series like this? At best, the Key was involved as nothing more than a McGuffin, powerful artefacts who only existed to give the baddies some sort of motivation. But in this story, the segment of the Key is the whole plot and has created the whole scenario that the Doctor and Romana find themselves in. As I stated before, Kroll had, at some point, swallowed the segment, which had caused him to grow very large and ravenous. This warps the Kroll religion into a vicious cult and has created vast methane reserves under the surface of the swamps, which has attracted the attention of greedy people from the planet, Delta-Magna, and is what inspires Thawn to try and wipe out the Swampies to get his hands at the wealth under the watery surface of the moon.
And this is exactly how the Key should have been integrated in the plot of every story from this series. As the Key is supposed to be a cosmic power with enormous reality altering abilities, it makes perfect sense that each segment should be very powerful in their own right and each story should have seen the Doctor trying to deal with whatever the segment had managed to do to the surrounding peoples, planets and landscapes, merely by them existing. A brilliant example of how they should have been treated is in the current Marvel comic book movies which see the Infinity Stones being collected by different characters. They aren't just plot devices but plot-chargers, something which bends the narrative around them whenever they appear.
Let's just go quickly back to the Avatar comparison I made earlier, there is a clear similarity between Kroll's moon and the planet in Avatar, Pandora. And the difference is also obvious. Pandora is a self-aware planet that actually cares about it's inhabitants, the inhabitants worship it and it protects them. Kroll is nothing more than a giant monster that will eat anything it can reach, no matter how much they worship it. This story is trying to be both a horror story and a tale an eco-political thriller. And despite Kroll's importance to the story, once he shows up, he actually ends up doing nothing but derailing the narrative. The conflict between the colonists and inhabitants becomes almost irrelevant as Thawn gets so paranoid he ends up putting aside his previous plans and spends the rest of his time trying to find ways to kill Kroll and hardly ever mentions The Swampies. Out of all the characters in this story, Thawn is the one who is most against the existence of The Swampies and yet, he never has a meaningful scene where he is seen interacting with one of them before he is killed with a spear. This just feels like one of those moments where the writer kills off the villain because there is only a couple of minutes left of the episode and he needs to clear the decks.
Also, the very fact that The Swampies are called, The Swampies, does prove that even Robert Holmes didn't know what to do with them and the lack of attention he paid to them as characters. It is the racist term by which they are know by the Delta-Magnans and used by Thawn that gives us no indication that this is what they call themselves. One of the real tragedy's of this story is that Holmes pays a real lack of attention to them, he doesn't give them a name, doesn't show any of their women or give them a culture which seems like a real thing and not a silly caricature. In fact, the only time he tries to flesh them out is by giving them their Kroll based religion. It mirrors King Kong and the way the natives of the island sacrifice Fay Wray to the gigantic gorilla. And while this scene is one of the most iconic in science-fiction cinema, it doesn't cast The Swampies in any kind of sympathetic light. This is a really fatal error for the story which is trying to portray them as the wronged party. But they have dozens of religious fanatics, several delusional tribesmen and one guy in a home-made squid costume, it doesn't allow us to feel any sympathy for them.
But what really lets this down is the terrible special effects. It isn't the Kroll monster but the puppet they used which lets the side down. The puppet with its moving tentacles looks convincing and the gurgling noise it makes can be pretty chilling. It is when we get tentacles bursting through refinery pipes that things get a whole lot less convincing. I suppose that the real problem isn't in the effects themselves, but the way they are used to blunt the dramatic impact that make them bad. Lets take the final cliff-hanger for the story at the end of episode 3, it should be an awe-inspiring as Kroll rises above The Doctor and Romana who are helpless in their little rowboat. Romana should have noticed something bubbling beneath the surface and shouted, "Look!". Then the giant squid should have risen out of the water as we watched, looming over our two heroes. Instead we get Romana looking down at the water, shouting and then turning back to see Kroll has already risen, and the pair are amazed to find they failed to notice a giant monster blotting out the sky. Just seeing that Kroll has already risen, renders the effects comical. And sadly, that is that all this story will be remembered for...