The Enterprise crew is hanging out one night, play poker. Sulu is winning everybody's Space Credits, and they're all getting pissed off because they didn't expect Sulu to be so good at poker. After several hours of losing, Spock is like "This is illogical, Sulu must be cheating. He is a total cheater." The room goes silent, and Sulu immediately flips over the table and pulls out his gun. "Did you just call me... a cheetah?" Spock doesn't get why Sulu is making such a big deal about this until Kirk whispers to him, "Dude, don't you know that Sulu's whole family was killed by cheetahs?" Spock explains that he actually called him a cheater and not a cheetah, because clearly Sulu is human and not feline, but it's too late because Sulu has already run out of the room crying. Everyone is like "Smooth move, Vulcan" and they tell him to go apologize to Sulu. Spock is like "Fine, I'll go apologize right after I finish this delicious Klingon Juice." Uhura whispers to Spock, "You said you were going to stop drinking so much" and Spock totally snaps at her, "You said you were going to shut the fuck up and suck my dick" which makes things pretty awkward for everyone else in the room. Scotty is so uncomfortable that he beams himself out into space and dies.
Later, Spock drunkenly shows up at Sulu's quarters to apologize. Sulu doesn't open the door when he knocks, so Spock tries to kick it open, but since they're on a spaceship with electronic doors that slide open it doesn't work, even when he uses a Flying Vulcan Kick. So then Spock just smashes open the control panel and hacks into the door controls and forces it to open up. He is about to apologize to Sulu, but before he can an animal claw scratches him across his face. And not just any animal claw, the claw of a cheetah. And the cheetah is wearing Sulu's uniform. Spock is like "Oh my god, you ARE a cheetah!" and the cheetah knocks Spock down and runs away. Spock hits his head on Sulu's statue of Buddha and gets knocked out. The next morning, Spock wakes up in the medical bay and he's all "Sulu is literally a cheetah, he attacked me with his claws last night!" Nobody believes him, especially Bones who is like "I refuse to give medical treatment to this lying motherfucker." Sulu comes into the room and shows Spock an X-Ray that proves he isn't a cheetah. Then Kirk is like "See, old friend? That's why Vulcans shouldn't drink. You lightweight pussy douche." And they all laugh except Spock, as the camera slowly zooms in on Kirk's eye to reveal that he has the eye of the cheetah, the thrill of the fight, rising up to the challenge of our rival.
That night, the crew are playing poker again. Someone asks where Uhura is, and Spock explains, "She said she didn't want to be around me when I drink Klingon Juice. Chicks, right?" Meanwhile, Kirk is winning everyone's money tonight, which Spock finds highly suspicious. He logically deduces that the cheetah must have transferred from Sulu's body into Kirk's body. He shares this theory with the others and they're all "Okay, whatever Drunky, go back to Drunktown." Spock says he'll prove that Kirk is really a cheetah, and all of sudden he grabs Kirk and starts making out with him. Everyone in the room is like "what the fuuuuck" and Chekov beams himself into space to escape the awkwardness. He was already wearing a spacesuit, so he survives, unlike Scotty whose frozen corpse floats right past Chekov. Back at the poker table, Spock and Kirk finally stop making out and Spock yells, "See? That proves he's a goddamn cheetah! Look at him!" But Kirk just looks normal, and he throws his cards down on the table. He wins again, this time with two pairs, and Bones is like "Yeah, two pairs of Vulcan balls in your mouth" Then everyone laughs except for Spock who realizes that the joke is highly illogical since Vulcans only have three testicles.
After the homoerotic space poker tournament, Spock goes to Uhura's room to try and prove that he isn't gay for Kirk. But Uhura isn't there. It's the cheetah, back for revenge. The cheetah shoots a laser net out of its eyes, which traps Spock so he can't escape. Spock is all "Dammit, who ARE you?" and the cheetah finally explains... He is Cheetro, the shape-shifting cheetah from planet Cheeton, and he has come aboard the Starship Enterprise to beat everyone at poker and start a new race of Cheetah/Vulcan hybrids. They will be called Cheecans. "You'll never get away with this, Cheetro!" yells Spock, but Cheetro isn't worried. "Please, Mr. Spock. I'm not a Science Fiction villian. Do you seriously think I would explain my master stroke to you if there were even the slightest possibility you could affect the outcome? I stole your semen 35 minutes ago." Spock is shocked: "So that was YOU jerking me off under the poker table! Damn you, Cheetro!"
"Anyways," says Cheetro, "Now that I've explained all that I just have to KILL YOU. Mwa ha ha ha!" Suddenly, Chekov crashes through the window on the back of Scotty's frozen corpse. Cheetro gets sucked into space but Spock is protected by the laser net. As Cheetro floats away he's like "Nooooo! Hoisted by my own petard!" Later that night, the Enterprise gang are all playing poker again, including Scotty, who Bones manged to resuscitate, but he still has severe brain damage from being in the vacuum of space for so long. Chekov keeps winning hand after hand, and Spock is once again suspicious, and is about to accuse Checkov of being a cheetah. But then he notices that he's actually reading a book called "How to Cheat at Poker, Vegas-Style." And Chekov pronounces it "Wegas-style". Everybody laughs at this, including Spock, because he is drunker than any Vulcan in the history of the universe. He has a serious drinking problem.