I disagree that you have to watch every episode of CSI. I do agree, however, that the first CSI (CSI: Las Vegas) is by FAR the best. Rather than suggest a season, I'm going to suggest episodes that you look into. I'll try and vary them from the seasons, so you can decide which one you want to watch. But if I HAD to choose a specific season, I'd have to direct you to season seven. Season seven was, in my opinion, CSI's best season ever, and you don't have to know the series to love it, really. Still, here are a few episodes from all of them that you can get into. If one sounds particularly interesting, ask me for a link and I can probably provide one to a place on the net where you can watch the episode for free.

Arcs and their Episodes

The Lady Heather Arc
Season 2, Episode 8: "Slaves of Las Vegas"
Season 3, Episode 18: "Lady Heather's Box"
Season 6, Episode 15: "Pirates of Third Reich"
Season 7, Episode 23: "The Good, the Bad and the Dominatrix"
Season 9, Episode 5: "Leave Out All The Rest"

The Serial Killers Arcs

"The Suicide Stager"
Season 1, Episode 1: "Pilot"
Season 1, Episode 8: "Anonymous"
Season 2, Episode 13: "Identity Crisis"

"The Blue Paint Killer"
Season 3, Episode 6: "The Execution of Catherine Willows"
Season 5, Episode 6: "What's Eating Gilbert Grissom?"

"The Miniature Killer"
Season 7, Episodes 1 and 2: "Built to Kill"
Season 7, Episode 7: "Post Mortem" (Cross-over with Demetrius James Storyline)
Season 7, Episode 10: "Loco Motives"
Season 7, Episode 16: "Monster in a Box"
Season 7, Episode 20: "Lab Rats" (Cross-over with Lab Rats storyline)
Season 7, Episode 24: "Living Doll"
Season 8, Episode 1: "Dead Doll"
Season 9, Episode 7: "Woulda, Coulda, Shoulda"

Lab Rat Romance Arc
Season 7, Episode 20: "Lab Rats" (Cross-over with Mini Killer storyline)
Season 8, Episode 8: "You Kill Me"
Season 9, Episode 20: "A Space Oddity"

Greg Sanders Versus Demetrius James Arc
Season 7, Episode 4: "Fannysmackin'"
Season 7, Episode 7: "Post Mortem" (Cross-over with Mini Killer Storyarc"
Season 7, Episode 19: "Big Shots"

The Hannah and Marlon Storyline/Sara's Exit
Season 6, Episode 18: "The Unusual Suspects"
Season 8, Episode 7: "Goodbye and Good Luck"

Warrick's Exit
Season 8, Epiosde 9: "Cockroaches"
Season 8, Episode 17: "For Gedda"
Season 9, Epiosde 1: "For Warrick"
Season 9, Episode 2: "The Happy Place" (Also Riley's Entrance)

Langston's Entrance/Grissom's Exit
Season 9, Episode 9: "19 Down"
Season 9, Epiosde 10: "One To Go"

I also made a list of stand-alone episodes for you here

For detailed descriptions on all of these, Click Here

If you would like a link to any of these episodes:

A) Search for it on Fanpop first.
B) If you can't find it, contact me.

ok just to start out with this c.s.i. is c.s.i.:las vegas!but yes they are all good but each of them has there own character lines and i think personally this one and miami are the best!but i think for the most part you would need to watch most of the episodes from the begining i mean its hard to tell which is important and which isnt and u would need to be able to follow the characters to understand where they are in there life now but no worries this season is coming to an end so you have all summer!!hope this helps good luck and they are amazing so im sure youll enjoy yoursell!!

i really started watching it from seoson 9 and if i didnt understand a part i read about the characters on wikipedia and if their was a good episode i watched it on fanpop. CSI is CSI las vegas and CSI NY is really good u can watch CSI miami if you want to its my fave but thats my opinion most ppl like CSI NY better

I would start with season one if you want to get the whole story line and everything, but CSI:NY is next to the best.

i think the best out of them is CSI NY i love it and gary sinise is in it i love him its one of my favourite tv shows