Where To Stream NCIS Los Angeles Season 4 Episode 20
Purity
- Aired April 9, 2013
- 60 Min
- Rated 7.0
- Number 280 Of 323 Rated Episodes
When cyanide in a communal water jug lethally poisons a lieutenant and leaves a Navy pilot in serious condition, the NCIS: LA team investigates whether this is an isolated incident or an early test for large-scale water contamination.