The episode opens with Lister on the bridge, enjoying a beer milkshake and a sappy film when he's interrupted by Holly, who is bored and needs Lister to erase some memory so that Holly can enjoy Agatha Christie novels again—having read everything, ever. Lister moves to his quarters to finish the film, but is interrupted again by Rimmer, being obnoxious as usual. Rimmer is aghast that Lister has gone down to the officers' block, as they haven't been sterilised yet - just because it was on Rimmer's "To-Do" list doesn't mean it was actually done. Lister was looking for Kochanski's dream recorder and talks about Petersen's theory of a person's Confidence and Paranoia, and how Paranoia always won when he wanted to chat her up. He tries to talk Rimmer into saying where he hid the other holo-disks, but Rimmer won't tell, not wanting to get switched off.
That night, Lister feels sick, tries to get to the medical quarters, and faints. Rimmer runs to the Cat for help. Cat immediately jumps to his feet—and then sits back down to keep eating once Rimmer has run out again, forcing Rimmer to employ the skutters. He's running a high fever from a virus that has spent three million years mutating in the unsterilised officers' quarters..
Later on, Lister's fever dreams become real, first as a rain of fish, and then as the titular Confidence and Paranoia. Paranoia is a sickly little man in a black suit who is mortified beyond compare at everything Lister does or has done. Confidence—played by Craig Ferguson—loves absolutely everything Lister does. Lister naturally loves Confidence, ignoring Rimmer's protests that they're symptoms. Rimmer tries to have Paranoia lethally injected while Confidence helps Lister figure out where Kochanski's holo-disk is: right outside the window of their sleeping quarters. Despite Rimmer's failure, Paranoia goes missing.
As Lister and Confidence go on a spacewalk to find the disk, Confidence casually reveals that he killed Paranoia (cha-cha-cha) for always tearing Lister down, and that Lister can do a lot better than a loser like him. In fact, Lister is so great he should just take his helmet off and relax—only losers need oxygen! An argument and a scuffle ensues as Lister naturally refuses. Confidence decides to show Lister how great it would be, removes his own helmet, and immediately blows up.
Shaken, but triumphantly in possession of Kochanski's disk, Lister plugs it in. It turns out... to be another Rimmer. Because like hell Rimmer would be stupid enough to leave Kochanski's disk in the envelope labeled Kochanski!
- Black Comedy Rape: Rimmer's liaison with Yvonne McGruder is brought up for the first time and it's...disturbing. It was given a slightly less squicky Retcon in the books.Rimmer: What about Yvonne MacGruder? That was a date.Lister: She'd been hit on the head by a winch, she had a concussion.Rimmer: That's got nothing to do with it. She was crazy about me.Lister: Oh, yeah? She kept calling you "Norman."Rimmer: She still went to bed with me.Lister: Yeah, because she had wonky vision and she thought you were somebody else.Rimmer: Serves her right for being concussed, doesn't it?
- Cassandra Truth (or likely Briar Patching): Rimmer solemnly warns Lister that he'll regret activating Kochanski's disk. He's right!
- Cats Are Mean: Cat can't comprehend why Lister needing help would justify interrupting lunch.
- Comically Missing the Point: Rimmer asks "What's going on?" and Holly replies that Poirot just stepped off the train, and in Holly's opinion they all did it.
- Crazy-Prepared: Rimmer not only hid the holo-disks so close by that Lister would never think to look there, he swapped Kochanski's disk with a duplicate of his own just in case Lister ever did figure it out.
- Exact Words: Rimmer never said he decontaminated the officers' block, just that he was planning to a few days ago.
- Explosive Decompression: Confidence explodes like a bomb the instant he removes his helmet.
- Eye Poke: One of the skutters does this to Lister while attempting to take his temperature.
- Glurge Addict: Lister indulges in a real sob-story of a movie and gets increasingly irritated that the best bit to cry over keeps getting interrupted.
- Going to Be One of Those Days: Rimmer says this in a very deadpan way after seeing the raining fish and the Mayor of Warsaw spontaneously combust.
- Good Angel, Bad Angel: Confidence and Paranoia. Although it's up for debate which is which
- Jerkass Has a Point: Rimmer correctly states that Confidence and Paranoia are symptoms of Lister's disease and therefore need to be gotten rid of.
- Kissing Warm-Up: Referenced when Paranoia starts dredging up Lister's embarrassing adolescent memories.Paranoia: Do you know he used to practice kissing on his own?Rimmer: How?Paranoia: (Demonstrating) He made lips out of one hand and waggled his thumb through the gap, like a tongue.Rimmer: That is priceless! It really is.Paranoia: Seventeen years old and he used to snog his own hand.
- Literal Split Personality: The titular personality traits manifest real people from Listers' mind. They then spend the rest of the episode trying to influence Lister until Confidence murders Paranoia and accidentally commits suicide
- Pet the Dog: Rimmer seems genuinely concerned about Lister's health.
- Rain of Something Unusual: Lister hallucinates a real indoor rain of fish, all of which are quickly eaten by the Cat.
- Reality Warper: A virus that's mutated over three millions years turns its host into one, with things that Lister talks about showing up in person.
- Shaped Like Itself: Rimmer tries to explain that Lister has been having "solid" hallucinations. Lister asks him to put it a different way, and Rimmer obliges...."You had hallucinations, all right? And they were solid."
- Suicidal Overconfidence: Confidence, in his efforts to build Lister up, says that he doesn't even need oxygen. Confidence takes off his own helmet to prove it.
- Take That!: According to Holly, the worst book ever written is Football: It's A Funny Old Game by Kevin Keegan.
- This Is Gonna Suck: Lister and Cat's reaction to having two Rimmers onboard.Rimmer: Think you had it bad before? Now you've got it in stereo, baby.
- Too Dumb to Live: Confidence removes his helmet in the vacuum of space. Big mistake.