When Dr. McCoy grumbles once too often about the way the USS Enterprise ought to be run, Captain Kirk puts him in command of the ship before beaming down for what is supposed to be a routine diplomatic mission. Then Kirk disappears, and McCoy (forbidden by regulations to relinquish command) is stuck in the hot seat overseeing a rapidly deteriorating situation that quickly acquires unexpected Klingons and goes downhill from there.
This novel contains examples of:
- Badass Boast: McCoy all but turns these into a language of their own in this book, as he never speaks to a Klingon in anything but one the whole time he is in command.If you use that tone with me again, my boy, I'll open your ship up like a sardine tin, and later on I'll fish your corpse out of space and thaw it out and stitch it back together the old-fashioned way, with a needle and thread, and then I'll use your guts for garters.
Think again, Commander. This is Enterprise. She is more than one man, though that one man may have made her famous—or among you, infamous. She is four hundred thirty-eight people—to whom you're an interesting enough problem, but one that we're long used to solving.
- Embarrassing Nickname: The planet's official listing in Federation Star Charts is "1212 Muscae IV". Most of the crew refer to it as "Flyspeck".
- Klingon Promotion: Invoked by McCoy when the Klingons want to know where Kirk is. Not wanting to explain the situation to an enemy, McCoy instead claims to have killed him in a duel and taken command.
- Language Equals Thought: It's mentioned that the Orion Pirates' word for "stealing" translates into English as "getting paid".
- Lost in Transmission: McCoy is initially relieved when the Klingons start jamming subspace communications and interrupt a tongue-lashing he's getting from Starfleet Command, until Spock points out that based on what the admiral was saying he was just about to relieve McCoy of command (and since the order was never actually received, Spock can't carry it out).
- The Master: Inverted with the Master of the ;At, who is Lawful Good and downright charming.
- Plant Aliens: The Lahit are basically walking fir trees. Upon seeing a group of them, McCoy snarks that Birnham Wood finally gets to come to Dunsinane.
- Pūnct'uatìon Sh'akër: Lampshaded. The first Federation survey team sent to a certain planet reported that one of the three sentient species there was called the ;At, but forgot to explain how the semicolon should be pronounced. At the beginning of the book, the Enterprise crew generally pronounce it as a click; later on, Uhura says that it's probably more of a glottal stop.
- Worthy Opponent: At the end of the book, the Klingon captain says that if all ship's doctors are like McCoy, then he should seriously consider having his own medical officer killed. McCoy replies that, based on his own diagnosis of the Klingon captain's medical condition, he should have his doctor killed anyway - either his doctor is so incompetent that he isn't able to diagnose the captain's clear signs of illness, or his doctor has diagnosed it and is already trying to kill him by providing substandard care.
- You Are in Command Now: McCoy is given the conn during a First Contact mission as part of a joke by Kirk. Then Kirk disappears into a temporal anomaly, a Klingon warship shows up, and Starfleet regulations won't allow McCoy to hand over command to any line officer until relieved by Kirk or Federation brass. He's not happy. Hilarity and awesome ensue.
- Discussed at length when Kirk decides to put McCoy in command - Kirk points out that while it is true that there is a chain of command, as Captain he has wide latitude to decide who to give the conn to in situations where there isn't likely to be any trouble.