The first season of CSI: Crime Scene Investigation (which I prefer to designate as "Las Vegas") includes 23 episodes total (if you get the Blu TVD set you'll get an additional director's cut of the pilot).
1) Pilot
Here’s the start of it all. Holly, is the newbie to the team. This is her first day which means she gets a bit of a hazing by Grissom, but that’s not the worst that will happen to her today. The CSI team investigates a death that appears to be suicide. The family has cast doubt on that thus increasing the need for an investigation. This is a huge challenge for Grissom who is not accustomed to being outsmarted, and it will come back to haunt him. Another case involves a father who says the guy he killed was threatening his family. The CSI's aren’t buying his story, but it will take putting the evidence together to find the actual answer.
-A great start and an interesting episode. The B story is more of a standard investigation, but the main mystery is one that is good enough to filter into other episodes later on.
2) Cool Change
A gambling couple wins a million dollars in a casino after which the guy decides his girlfriend is an unwanted burden shortly before he turns up dead. Grissom takes over leadership of the CSI night shift and sets out to crack this case. Warrick takes what happened to Holly hard and for good reason since he was partly to blame. Sara is brought on board to investigate exactly what happened which leads to Warrick getting into trouble over his gambling addiction.
3) Crate And Burial
A woman is missing and a ransom leveled on her husband. Why doesn’t he want to cooperate with the authorities? Meanwhile a hit and run lands an elderly man in hot water, but Warrick forms a bond with the family.
4) Pledging Mr Johnson
Fisherman find a leg in a lake leading to the discovery of a body attached to some serious marital troubles. Meanwhile a frat pledge appears to have hanged himself though the CSI’s can’t help but suspect a hazing gone wrong. As they investigate a judge blackmails Warrick into tampering with evidence.
-The return to Warrick's problem is a good character moment.
5) Friends And Lovers
A naked guy in the desert drops dead running from something. There doesn’t seem to be any logical reason for him to be naked, in the desert, or dead. Meanwhile, Sara investigates a body found in a dumpster. The dead woman’s funeral was a week ago. So how did she go from grave to dump? Grave robbing perhaps? And we get a third story this time with a woman who clubs a man to death in a school claiming self defense. Catherine is not sold on the story and sets out to see what the evidence corroborates and what it doesn’t.
6) Who Are You
A corpse is discovered buried in the foundation of a house. It’s been there so long the CSI’s don’t even know who it might be which makes it hard to investigate. When they bring in a forensic artist Grissom seems to have his eye on her. Meanwhile, Brass gets defensive over an apparent suicide that involves a police officer. Once again with a third story, Catherine’s ex-husband is a suspect in another case. Grissom orders her to hand it off, but she can’t seem to bring herself to do it.
-The ending to this one is particularly explosive. It's also an interesting look into Catherine's troubled family life.
7) Blood Drops
A family is killed in their home leaving only 2 girls alive: a teen and a very young child. It’s veritable bloodbath with the only clues being a pattern drawn in blood and the cryptic mumbling of the young child. The deeper the CSI’s go the stranger the case becomes. As the case unfolds Catherine’s ex tries to make nice and Grissom clashes with Eckley for the first time.
-I would say this is one of the most powerful episodes ever. It both deserves and requires the full focus of the episode without another side case.
-A young Dakota Fanning guest stars.
8) Anonymous
Harkening back to an earlier episode, another man appears to have committed suicide in a tub. Grissom makes this case his mission. Has our Sherlock met his Moriarty? Meanwhile the other team members investigate a car at the bottom of a cliff, one that’s missing its driver.
-The B story this time seems to be more comic relief for the dark A story.
9) Unfriendly Skies
A guy dies aboard a plane during a flight, and while everyone in first class knows what happened not one is forthcoming. What happened on that plane? The facts told by the evidence and stories told by the witnesses do not add up. With limited time for investigation the challenge increases with each puzzle piece.
-James Avery and Glenn Morshower have small roles.
10) Sex Lies And Larvae
A couple of hikers find a desiccated corpse. With evidence minimal Grissom turns to entomology for his first clue. It leads to a possible but unconfirmed case of domestic abuse to which Sara immediately reacts harshly. Meanwhile other CSI’s investigate a robbery that looks to be an inside job and a missing woman that Nick figures to be a dud until he finally finds that first bit of elusive evidence.
11) I-15 Murders
When a woman disappears from a supermarket the writing on the wall (literally) suggests a serial killer. Grissom confronts Warrick about gambling on company time and Sara passes her judgment on both of them without bothering to learn all the facts. Nick is called on for help by a prostitute from a previous case who is being charged with assault.
12) Fahrenheit 932
A fireman on trial for murder by fire calls on Grissom for help in clearing his name. Undertaking this means crossing Eckley (again), but Grissom can’t help himself. While the case looks tight on the surface, Grissom quickly uncovers unanswered questions, though that doesn’t mean it’s in the fireman's favor; he is covering something up even if it isn't murder. Meanwhile a young guy is shot in his car in a parking deck. Warrick’s experience with gambling might come in handy for once as the kid was mixed up in that world, himself.
13) Boom
A bomb goes off in a building’s lobby. An overzealous security guard seems to know an awful lot about bombs. Is he a would-be hero with an obsession and lack of sense, or is he a villain using heroism as a cover? Meanwhile, Nick crosses paths with his hooker friend again, once more coming to her rescue. This leads to a personal involvement that ends badly and lands Nick under suspicion for murder. Eckley sets out to make this the end of Nick as a CSI.
14) To Halve And To Hold
A single leg bone leads Catherine to suspect a murder, but Grissom thinks she’s jumping to conclusions. The search for more bones in the desert is on. Meanwhile, a male dancer is murdered in a hotel room after a bachelorette party with the prime suspects being a kindly old lady and the entire female wedding party.
15) Table Stakes
A charity fundraiser dinner turns deadly. With a party this size the number of suspects is staggering, and just trying to question everyone promises to be an arduous task. Meanwhile, Warrick investigates what appears to be a professional hit.
16) Too Tough To Die
Catherine’s ex is causing more trouble for her right when she’s trying to deal with a messy case that’s going to trial soon. Was her case one of murder of self defense? Despite the stress in her home life it’s Catherine’s job to make sense of the evidence for the DA, but the stress only ratchets up when evidence is misplaced.
17) Face Lift
A store robbery in the night has left behind a corpse. The investigation turns up evidence of a long missing girl – a case that long been considered to be cold. Meanwhile, Sara thinks she may have uncovered a case of spontaneous human combustion although everyone else thinks the husband murdered the woman.
18) $35K OBO
A couple returning from a night out is murdered in the street. When CSI shows up a torrential rain destroys the scene which makes them have to work that much harder for the answers to what happened. Meanwhile, Catherine investigates a house that collapsed causing fatalities. She’s determined to find out who’s to blame. Surprises start jumping out at them all.
19) Gentle Gentle
A baby is kidnapped right out of the crib and ransom demanded. Friend or stranger? The case hits everyone hard and emotions run high. Grissom in particular seems to have a hard time with it.
20) Sounds Of Silence
A couple of girls run over some poor guy. But what’s this? He was already dead? Turns out he was deaf. Does this mean his death was an accident caused by him not hearing a vehicle, or was it a vicious murder? The CSI’s clash with his school as they attempt investigation. Grissom proves to be good with dealing with the school but bad with administration of his own people. Meanwhile, across town, a coffee shop has been shot up leaving several dead, but to figure out what happened the team is going to have to trace the exact path of each and every bullet.
21) Justice Is Served
A jogger is mauled by an animal but human involvement is evident. The case leads to a woman with a nutrition obsession and some strange concoctions. Meanwhile, a young girl is killed at a carnival, and Catherine is all over it. She’s ready to hang half the carnies there as soon as she steps foot on the grounds. Investigation is merely a formality, but she'll have to get past her prejudices to catch a killer.
22) Evaluation Day
It’s evaluation day and Grissom is checking out his team. A couple of half-naked, half-crazy girls are pulled over by police. Investigation reveals a head in the trunk of the car. Warrick investigates a murder in Juvenile Hall that involves a kid he befriended during a previous hit and run investigation. James can’t tell Warrick what happened as the other inmates will hurt him for doing so; they have to put their faith in science to reveal the story and clear James' name.
23) Strip Strangler
Someone is strangling girls in their homes. The CSI’s are all over it, but the guy is good and leaving them no clues. The sheriff brings in the FBI which makes Grissom less than happy. They want to bait the killer using Sara, and the sheriff, tired of dealing with Grissom, moves towards replacing the entomologist with Catherine.
-We have seen something like this already this season with a serial killer and a mystery man who is able to work the system to avoid detection. This one, though, is focused more on the fallout from Grissom's political disagreements. It's interesting to see how he handles this.