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8 Times Leonard “Bones” McCoy’s Medical Knowledge Saved The Day

“I'm a doctor, not a bricklayer!”

McCoy Cover

He’s a sounding board for the captain and a sympathetic ear for his crewmates. For the audience, he’s a stand-in that reminds us that space is disease and danger wrapped in darkness and silence, but that humanity is going to make it.

He’s assisted in births both humanoid (“Friday’s Child”) and not (the Gorn birth alluded to in Star Trek Into Darkness), cauterized a penetrating wound with a hand phaser (Star Trek Beyond), created a vaccine while the Enterprise is in a death spiral above a dying world (“The Naked Time”) and put up with a certain half-Vulcan science officer continually putting him in his place.

He’s the man of the hour, Doctor Leonard McCoy, and here are eight times his medical prowess saved the day.


McCoy Miri

Captain Kirk, Spock, Dr. McCoy, Janice Rand, and two crewmen beam down to a world that’s an exact replica of Earth in the middle of the 20th Century.  The cities are near-empty, with just two small groups of survivors fighting for life: human children (“Onlies”) and the strange humanoid wretches they call “Grups.” The team discovers that the strange circumstances are the result of a pathogen unleashed by a medical experiment in prolonging longevity gone wrong and they’ve all been exposed.

You can probably guess what happens next: the landing party now has a ticking clock tied to their survival (except for Spock, who’ll get to live the rest of his life as a carrier surrounded by preteens) and McCoy undertakes a desperate quest to isolate the organism responsible for their condition and find a cure.

Despite overwhelming circumstances  — the conditions are primitive and the leader of the Onlies, Jahn, steals the landing party’s  “little boxes” at one point, stranding the doctor without a vital connection to Enterprise’s computers — Bones manages to find the organism responsible and synthesizes what he thinks may be a vaccine.

When presented with the possible cure, Spock immediately pulls a Spock.  He states flatly that the vial might also be a beaker full of death since they can’t determine dosage and are unable to check their data. McCoy responds by injecting himself to test the cure and prove the Vulcan wrong.

Thankfully, he survived, but how weird would it have been if his Hail Mary pass hadn’t worked and they had to replace McCoy so early in the series?

"The Devil In The Dark"

Devil in the Dark McCoy

Miners on Janus VI have been stricken by a series of mysterious melty deaths, and the Enterprise answers their distress call to look into the situation and find the cause. They soon discover the Horta, an acid-emitting, silicone-based creature that’s been wounded in a series of escalating conflicts between the humans and herself. Spock, again, pulls a Spock and decides to go ahead and mind-meld with her and discovers that she’s just trying to protect her babies. Kirk sizes up the situation and calls McCoy down to help the hurt alien.

McCoy examines the rocky-skinned patient and delivers one of the most iconic lines of the franchise: “I'm a doctor, not a bricklayer.”

Ironically, if he left the medical profession, Bones would make a heck of a contractor. After beaming down “a hundred pounds of that thermoconcrete. You know, the kind we use to build emergency shelters out of,” he trowels the silicone-based construction material into the wound, where it will act as a bandage until she heals.

“By golly, Jim, I'm beginning to think I can cure a rainy day,” he informs the captain.

"Amok Time"

Amok Time McCoy

Defying orders, the Enterprise diverts to Vulcan to help Spock, who is is suffering from pon-farr, a crippling biological urge that his species undergoes every seven years.  It’s only after reaching the planet that the first officer reveals that he’s married, making it the first time that one of Spock’s familial secrets is revealed, but certainly not the last.

Unfortunately, it’s not just a matter of mind-melding with T’Pring to relieve the plak tow blood fever, because she’s opted for kal-if-fee, in which Spock will have to fight for her love. She chooses Kirk as her champion instead of Stonn, the Vulcan man with whom she wants to be betrothed. (One supposes that this is the sort of thing you do when you want to make the whole infidelity thing just that much more difficult for everyone.)

Kirk and Spock enter combat with one another using traditional weapons and, unsurprisingly, the Vulcan quickly asserts his physical superiority. After the first round, McCoy asks for permission to inject the captain with a tri-ox compound to help him compensate for the planet’s thinner atmosphere. That doesn’t help as much as anyone would like, as Spock still strangles his best friend, whose body is quickly beamed up.

Spock, shocked at the ritual murder he’s just committed, snaps out of the plak tow and lets T’Pring know that it’s fine if she wants to run off with Stonn now, because he’s done with her drama. He returns to the ship and ignores McCoy’s attempts to explain something to announce that he has the intention of turning himself in for court martial. That’s when Kirk steps out from the shadows and asks if the first offer should maybe ask the captain first before doing that sort of thing.

What happened? It wasn’t tri-ox in the doctor’s bag of tricks, but a nerve paralyzer that slipped Kirk into a state that simulated death. This makes us wonder, though - what else is in McCoy’s tote?

"Journey to Babel"

journey to babel mccoy

Stardate 3842.3: Just nine episodes after “Amok Time,” the Enterprise returns to Vulcan to pick up Ambassador Sarek as part of a diplomatic party that’s being transported to Babel, a neutral planetoid perfect for negotiations. To the surprise of Kirk and McCoy, it’s revealed that Sarek is Spock’s estranged father.

(Can’t this guy just talk to his friends sometime? Maybe give them a heads-up on things like fathers and wives and all that?)

The following things occur in short order: a mysterious vessel is discovered trailing the Enterprise; an argumentative Tellarite diplomat is murdered using a Vulcan technique after twice confronting Sarek about his forthcoming vote; Sarek is questioned about Gav’s death and succumbs to a previously-unrevealed heart condition that can only be cured through surgery that requires Spock’s presence as a blood donor; a signal is sent from the pursuing vessel to somewhere on the ship and Kirk is stabbed and left incapacitated by an Andorian diplomat, Thelev.

Just another Tuesday on the Enterprise.

Thelev is quickly arrested but there’s still that mysterious vessel to deal with. Spock finds himself duty-bound to sit in the center seat against his mother’s and the doctor’s wishes. His dilemma is quickly solved when a seemingly-recovered Captain Kirk shows up with the intention of handing the ship over to Scotty and retiring to his quarters while Spock undergoes the blood transfusion. Of course, it doesn’t work out that easily.

McCoy performs cryogenic open-heart procedure with a donor who’s using an untested Rigelian stimulant to induce blood cell production while the ship is repeatedly rocked by phasers and photon torpedos. There are multiple power failures and Sarek suffers a cardiac arrest, leaving Bones and Nurse Chapel to use portable equipment to keep him alive while the rest of the ship deals with the whole “Fake Andorian Who Turns Out To Be A Romulan Spy Who Is Working To Disrupt The Babel Conference” situation.

Once things are sorted on the bridge, Kirk returns to sickbay to brief the ambassador and his son, who are now chatting away as if they hadn’t spent the last 18 years trying to out-freeze each other. Not only can McCoy perform space battlefield surgery, he can restore families and, after the Captain collapses and is ordered onto a bed, finally get the last word.

"The Enterprise Incident"

Enterprise incident McCoy

“Enterprise Medical Log, stardate 5027.3. Doctor Leonard McCoy recording. I'm concerned about Captain Kirk. He shows indications of increasing tension and emotional stress.”

You’re telling us, Bones. This episode starts with the above quote and we cut to Kirk going off the deep end and ordering the ship across the Romulan neutral zone. That goes about as well as you’d expect; Kirk and Spock are soon aboard the Romulan flagship and facing possible execution for their crimes.

Kirk suffers a paranoid breakdown aboard the other ship, accusing Spock of being a traitor after seeing how well the Vulcan and the Romulan commander are getting on. McCoy is beamed over to examine him. It’s during his ministrations that Kirk suddenly leaps up and attacks his first officer, who defends himself with the never-before-seen Vulcan Death Grip, killing him instantly.

In the sick bay, it’s revealed that the entire episode so far was what experts in drama refer to as “a total fake out” and that Captain Kirk is alive. In fact, he’s about to get some high-quality otoplasty and eyebrow work courtesy of Bones in order to pass as a Romulan. His actions and Spock’s are for the sole purpose of helping Starfleet get its hands on the cloaking device that has plagued them for the last several years.

What’s interesting about this episode is that it depends on so many things going right that one slip-up could have led to the whole house of cards collapsing. Additionally: just how much does our favorite doctor know? Is he in on it from the start or does he start to improvise aboard the Romulan vessel once he realizes that Kirk’s not really dead?

"Spock’s Brain"

Amok Time McCoy

This episode is part of the pantheon of TOS episodes in which someone boards the ship and does something inconvenient. In this case, it’s stealing Spock’s brain, which is very inconvenient indeed. The residents of Sigma Draconis VII need the Vulcan’s high-powered skull meat to serve as the controller for their vast underground dwelling, and that’s why Kirk, McCoy, Scotty, and the remote-controlled body of Spock find themselves there.

They finally get in touch with Spock’s mind and he informs them that while he, “might trust the doctor to remove a splinter or lance a boil,” he doesn’t believe that McCoy or indeed anyone has the requisite skills to restore his brain’s place in his body. Kirk rightly figures out that if someone from the planet managed to remove the brain, they probably know how to put it back, too.

This leads our rescue party to “the teacher,” a device used to impart knowledge for a period of about three hours. McCoy’s never performed an encephalplexy before but he has supreme faith in his abilities to get the procedure done in that time with the help of the teacher. Spock, of course, disagrees, but the doctor’s desire to prove him wrong again proves to be a strong motivating factor. Even as the knowledge fades from his mind, McCoy’s competence keeps the patient alive and, eventually restored to his proper place.

Side note: in Gene Coon’s original outline for the episode, McCoy received no alien knowledge directly, he just studied their techniques conventionally and was able to mimic them. This would have made McCoy’s surgery even more miraculous.

"Star Trek IV: The Voyage Home"

Voyage Home McCoy

If you had a present-day doctor go back to the early 1700s, they’d likely be aghast. Smallpox, cowpox, and measles ran rampant, homeopathy was viewed as a perfectly reasonable course of action, and if you burnt yourself, it was likely that you’d be told to use an ointment that included, “mosse that groweth on an old thackt howse top.”

With this in mind, it’s easy to imagine how a doctor from the 23rd century felt when visiting a hospital in San Francisco in 1986 and being told by an elderly woman that she was undergoing kidney dialysis.

For the unfamiliar, dialysis is a treatment that occurs at the end stage of kidney failure, when the organs have have lost 85 to 90 percent of their function. Dialysis removes waste and helps the body maintain its blood pressure as well as its levels of potassium and other essential chemicals, which is good, but the average person only lives for an additional five to ten years. The only alternative at the present is a kidney transplant, which comes with its own complications including outright organ rejection and a recovery period of three to eight weeks.

Bones’s immediate response is, “Dialysis? My god, what is this, the Dark Ages?” He hands her a pill, saying, “Here, you swallow that. If you have a problem, just call me,” before going to rescue Chekov from a group of surgeons who are literally about to drill a hole in his head.

When next we see the patient (when Kirk, Gillian, and McCoy are trying to wheel Chekov out of the hospital), the understandably delighted woman is informing a group of flustered doctors that the pill he gave her grew a completely new kidney.

Remembered when I wondered what else was in McCoy’s bag? Turns out it’s full of replacement organs. For Bones, I’m sure it was another Tuesday, but I’d love to see what the  Journal of the American Medical Association had to say about the whole thing.

Star Trek (2009)

McCoy, holding an ill Kirk up, addresses a Starfleet official in Star Trek (2009)

In the Kelvin timeline, Bones saved the Federation. No big deal.

Seriously, without his absolutely encyclopedic knowledge of alien diseases, he never could have gotten Jim Kirk sick enough to have him brought aboard the Enterprise under his care.

Sure, his hands are grotesquely swollen as a result of the vaccine against against viral infection from Melvaran mud fleas and his tongue goes numb as a result of the cortazone that McCoy administered to counter the inflated hands, but Kirk is able to warn Pike and the Enterprise arrives at Vulcan with its shields up and under red alert, giving them an advantage the rest of Starfleet didn’t have.

Without McCoy’s knowledge and ability to act on it, Nero and crew of the Narada could have rampaged across the galaxy, crushing planets with impunity as long as they had red matter to play with. That makes this a perfect place to wrap up the article, as there’s just no way we can beat that.

Kevin Church (he/him) lives in Brooklyn, NY with his partner Robin and two small dogs. He writes comics, takes pictures, and occasionally updates They Boldly Went, a Tumblr dedicated to The Original Series. Follow him on Twitter @Kevin_Church.