Critics from TV Fanatic rated the episode a 4.2 / 5.0 , praising the strong team interaction and the focus on core cast members rather than outside guest stars. While some plot points were deemed predictable, the ideological conflict presented by the DNA group added a layer of complexity often missing from standard procedurals. NCIS: Los Angeles Season 4 Episode 20 Recap: Purity
: G. Callen (Chris O'Donnell) infiltrates the group by staging a public brawl with Sam Hanna (LL Cool J). This leads to a tense sequence where Callen's cover is blown, and he is nearly killed by the very cyanide he's investigating, only saved by a timely counteragent. NCIS.Los.Angeles.S04E20.HDTV.x264-LOL.[VTV].mp4
Review: NCIS: Los Angeles Season 4, Episode 20 – "Purity" "Purity" is a high-stakes, technically intriguing episode of NCIS: Los Angeles that leans heavily into the team’s undercover capabilities. Originally aired on April 9, 2013, the episode centers on a domestic terrorism plot involving cyanide poisoning. Critics from TV Fanatic rated the episode a 4
The investigation begins when a Navy lieutenant is lethally poisoned by cyanide in a communal water jug. The team quickly discovers this was merely a trial run for a much larger attack by a radical protest group known as "Designing a New America" (DNA). Their goal—allocating the defense budget to education—is noble on the surface, but their method is murderous. Standout Moments & Character Dynamics Callen (Chris O'Donnell) infiltrates the group by staging