Every so often, CSI goes for a lighter touch. Sometimes it's successful, and sometimes it's a mess of zombie jokes and puns about the psychedelic sixties. Guess which one "Turn On, Tune In, Drop Dead" turned out to be?

It's understandable that, to keep suspense built and viewers eager in the aftermath of Nate Haskell's escape, ploys would be used... but zombies? Really? Has the creative team run out of ideas?

The zombie phenomenon was explained away as merely the after-effects of a paralytic neurotoxin mixed with psychotropic drugs. The three students involved - two of which were proclaimed dead, only to rise up and lurch away - were continuing the pseudoscience research into the afterlife once conducted by Dr. Elliot Davis Aden.

Dr. Aden ended up being really nothing more than a walking cartoon of purple prose. He was presented as a clown, and when it came time to see him as dark and menacing, it was hard to take him seriously. Impossible, really.

I'm hard pressed to believe that - even with the aid of a paralytic - trained professionals would not notice that someone was actually alive. Ray spotted pupil dilation on Dr. Aden at the very end of the episode, so why didn't the paramedics?

Oh, that's right, Doc Robbins made it clear that the paramedics in question are slightly negligent. The paramedic didn't have her equipment properly calibrated, which was meant to lead the audience to believe she was incompetent. The paramedic in question doesn't even really get in trouble. She just got a stern talking to that turned into yet another undead joke.

I did appreciate the two minutes taken at the beginning of the episode to remind me that one of worst serial killers in history had escaped. It actually would have been nice to see some of the manhunt in action, even as a secondary story. The extra focus could have been used to shed light on Ray's emotional state, instead of the fleeting angry looks and a mini pep talk by Doc Robbins about the dangers of the good being dragged into the dark.

What did everyone else think?