“Obsession” is easy to describe. It’s Kirk as Captain Ahab. We’ve seen Commodore Decker play this role in “The Doomsday Machine“, but now it’s Kirk’s turn. He goes on a blind rampage of revenge against a mysterious gaseous creature that sucks the red blood cells from its victims.
The story opens with not one, but two redshirts biting the dust to the creature, during a survey of Argus X for the mineral tritanium, which is 20 times harder than diamond (or “21.4 times harder, to be precise,” as Spock says). That plot element is dropped as soon as Kirk detects a sickly sweet odour, which reminds him of an incident 11 years earlier, in which 200 crew members of the USS Farragut were killed by a weird gaseous entity that gave of a similar smell. Kirk blames himself for the deaths of the crew and quickly turns obsessive about tracking down and killing the “creature”, as he calls it. He does so despite having a deadline to meet another ship to transfer desperately needed medical supplies, ignoring direct Starfleet orders in the process.
This causes McCoy and Spock to team up in confronting Kirk. McCoy is about to declare Kirk unfit to command,with Spock’s back-up, but Kirk argues them out of it with logic. He points out that the creature is a known killer and has space travel capability, so is a threat to the Federation. This is enough for the time being, but Kirk is eventually proved correct later when it turns out that the creature is about to spawn, generating thousands of copies of itself. They chase it through space, but it turns on the Enterprise, making use of a Chekhov’s gun mentioned earlier by Scotty – an impulse engine vent that has been opened for repairs. For some reason, entering this vent gives the creature access to the life support ventilation system – so apparently the air circulation system is directly connected to a vent that opens to space?
What’s more, a room vent is left jammed open by Ensign Garrovick (the son of the captain of the Farragut, who died in the earlier incident and for whose death Kirk blames himself), allowing the creature into the ship proper. Fortunately Spock keeps it at bay with his Vulcan blood, containing copper rather than iron-based haemoglobin. Eventually they confront the creature on the planet Tycho IV, which is where the Farragut incident occurred. They decide to blow it up using antimatter, and Kirk and Garrovick take on the suicide mission of escorting an antimatter bomb and baiting it for the creature. They plan to use artificial blood as bait, but the creature eats it all before the bomb is ready, so they need to lure it themselves. Cue a fistfight between Kirk and Garrovick as the ensign wants to sacrifice himself to kill the creature that killed his father, while Kirk wants to save Garrovick. The creature approaches close enough to almost kill them before they both beam away and detonate the bomb, causing some hairy moments with the transporter before they appear safely aboard the Enterprise. This gives McCoy the chance to display his distrust of the transporter: “Crazy way to travel”. One wonders, however, why they had to lure the creature right on top of the bomb, when they said it was equivalent o “100,000 cobalt bombs” and would “rip half the atmosphere off the planet“. Surely detonating when the creature was… a whole 20 metres away and Kirk and Garrovick could have beamed back perfectly safely would have been just as good.
Other notes: Kirk has some interesting African style artefacts in his quarters. Garrovick gets served some food, which is a delectable looking plate of shapeless primary coloured blobs. And finally, the perennial extra, Lieutenant Leslie, was one of the redshirts summarily killed by the creature in the pre-credits sequence. Yet later in the episode he is seen walking around the backgrounds! And he appears in later episodes too. Canonically this is explained as him “recovering” from his not-quite-dead state, despite him clearly being declared dead. Overall, an okay episode, with a decent enough story, but nothing particularly special or memorable.
Tropes: Revenge Before Reason, Fog Of Doom, Our Vampires Are Different, Red Shirt, Ludicrous Precision, His Story Repeats Itself, Guilt Complex, My Greatest Second Chance, Screw The Rules, I’m Doing What’s Right, The Hunter Becomes The Hunted, Chekhov’s Gun, Wallbanger, Percussive Prevention, More Hero Than Thou, Atmosphere Abuse, Food Pills.
Body count: An unnamed redshirt and redshirt Lieutenant Leslie, redshirt Ensign Rizzo, another nameless redshirt, then another nameless redshirt, and finally the gaseous creature.
Maybe they were afraid the creature could … dodge? (And that’s Leslie’s twin brother!)