After Romulans chase the Enterprise through an energy cloud, the ship is plagued by a series of silly pranks.
Plot Summary: While surveying an asteroid field, an unexpected attack by three Romulan warships drives the Enterprise into an unknown energy field. Soon afterward, diners find that their cups have holes and Spock finds a new microscope that gives him black eyes. Kirk soon shares Scotty’s anger that someone on the crew is using the computer to play practical jokes, but when the computer itself bursts into laughter, Spock realizes that the computer alone is responsible for the pranks, having been corrupted by subatomic particles from the energy field. Minor gags like a food-tossing replicator are followed by more dangerous ones, like laughing gas replacing the ship’s oxygen and several crewmembers being trapped in a holographic simulation that subjects them to extreme climate changes. When Scotty tries to reroute ship’s systems, the computer turns off the artificial gravity, then taunts the Romulans by tricking them into attacking a giant balloon. Kirk announces that he is terrified of returning to the energy field in which they hid from the Romulans before. Seeing an opportunity for another prank, the computer heads into the field, but the joke is on the computer, for upon returning to the energy field, the subatomic particles leave the Enterprise, restoring the computer to normal. Meanwhile, the pursuing Romulan ships become infected with the same subatomic particles, and as the Enterprise flees, they hear over the comm that the Romulans are knee-deep in food.
Analysis: While there are no scientific or speculative virtues to “The Practical Joker,” it is a favorite of many viewers for two reasons: it features the first canonical appearance of a holodeck in the Star Trek franchise, and it shows our handsome, confident captain wearing a “Kirk is a Jerk” shirt. So most of the other pranks are at the level of 10-year-old humor…who cares? At least their aren’t exploding toilets, though one rather wishes that Scotty had laughed appreciatively at M’Ress and Arex when he thought they were responsible for a replicator tossing food at him instead of getting cranky and blaming them. As is typical, the crew’s annoyance only encourages the practical joker’s efforts, which then escalate to create real dangers like an ice field on one of the Enterprise’s decks.
Okay, so there are big plot holes like the fact that we never find out why the Romulans were waiting to ambush the Enterprise, and it’s unfortunate that the holodeck malfunction is introduced in the very same episode that introduces the holodeck because Star Trek: The Next Generation used that plot device long past its entertainment value. Wouldn’t it have been joke enough to have McCoy, Uhura, and Sulu goofing off in some exotic locale without ever being able to hear the summons as medical, communication, and tactical crises arose all over the ship? Instead it’s Arex who’s on the bridge when the laughing gas comes through the air ducts, which isn’t as funny as it would have been to see Sulu and Uhura doubled over in hilarity as Spock tried to save them.
I readily admit that I love hearing the computer demand that Kirk say “pretty please” and replying to his questions with answers like, “That is for me to know and you to find out.” Majel Barrett does a lovely job with the computer voice, which still sounds stiff and mechanical enough to be quite funny when it’s making outrageous statements, and Kirk’s sputtering fury just makes it funnier…though I do wish Spock had tried to debate logic with it when it goaded the Romulans, since the destruction of the Enterprise would have had an adverse affect on its systems and since I’ve no idea what it would have done with “Logic is a little tweeting bird chirping in a meadow.” No, there’s not a lot of depth, and arguably it was a poor choice to air “The Practical Joker” so close to “Bem” considering that the latter featured a prankster of sorts as well, but who cares? “Kirk is a Jerk,” indeed.