Okay, I've already reviewed the season opener to CSI, but seeing as that was a two-parter, I thought I'd just add in a bit more non-spoiling detail.
With CSI up against soapy old Grey's Anatomy in the US on Thursdays, there's a fair old amount of soap turning up in CSI to match. Catherine's being put through the wringer for this two-parter, but the general aim of the season is to show the effects of investigating crime on all the CSIs (what a good idea for a show. Why don't we call it Touching Evil? Oh wait...).
There's also an unsolved crime that I suspect will return during the rest of the season. One of the more disturbing things about this two-parter is the “doll's house” crime, in which a crime scene is lovingly recreated in an exact model left at the scene itself. Since even the blood pattern in the doll's house is the same (and it's made with the victim's blood), we know we've got an absolute nutbag here.
I can't help but feeling there's something similar to the serial killer in the first season at work here, but since that was intellectually fascinating storyline, I'm none too fussed by that.
All the same, some intriguing things at work that should make season 7 of CSI a very interesting one. My only worry is they might push everything into realm of highly, highly implausible if they're not careful.
PS Episode two has a highly upsetting ending. Brace yourself.