“Grace Period” involves Special Agent Paula Cassidy, who’s been something of a recurring character, in a terrorist chase. “Cover Story” reveals that McGee is working on a new book (he writes fiction and his first book was a bestseller that allowed him to buy a sports car as well as other boy toys) and the murderer appears to be following some of his script. “Brothers In Arms” advances one of the many subplots of the season when Jenny Shepard starts digging into her spy father’s secrets.

“In The Dark” is a straightforward mystery again, but it’s got some neat characterizations and twists. “Trojan Horse” has a plot that reflects the title, and this one gets a little too convoluted. “Angel of Death” brings in Shepard’s father’s past in a big way, and it sets up the season’s cliffhanger.

NCIS Season 4 is a must-buy for fans of the show who collect the episodes. But it’s a great place for viewers new to the show to begin. With four years under its belt, NCIS has a lot of history, but you can catch up quickly.

I really enjoyed season four, even with all the complexity and "one hand not knowing what the other hand is doing" machinations, but I’m glad season five is returning to the standalone episodes and no ongoing plotlines. These characters are some of the best on television, and the writers are really good.