When two victims are linked by a very unusual weapon, the CSI team tries to solve the puzzling mystery.
The best part of this episode for me was the last 7 minutes. I have always loved Sid and it did not surprise me that he turned out to be the Guardian Angel. Sid never seemed to that affected by new found wealth, so it made perfect sense to me that he'd want to do something useful with what he had. Robert Joy did a great job with this scene.
I get the feeling that the writers of the show are starting to head in the direction of wrapping things up for good. The last episode of this season airs in February and I don't think that bodes well for another season.
I did like the use of the 3D manufacturing process to make a gun. This technology already exists for machining some parts, so it makes sense that someday soon it will be used for other purposes. I recall Mac using the earlier version of this process in the "Officer Blue" episode way back in season one or two when he recreated a 3D bullet.
The ballistics chamber was different than what we've seen in the past. I can't recall a time when anyone stuck their hand into a protective glove behind a plexiglass chamber. It reminded me of what you would use to handle toxic chemicals or pathogens.