With the two-hour season finale of Dark Blue next week (actually two separate episodes, I assume, to avoid network competition), there's not much to expect in terms of overall story developments. The main problem of Dark Blue is the writing. The typical episode: buy-and-bust, problem, slick talking, arrest and/or shoot bad guys. And the only difference in the second season is that there's "drama" with Carter and Alex, and less reckless behavior--knocking down doors, scrounging for money.
Behind Carter and Alex, Ty has the next most development, and "Shell Game" has good focus on him, putting him in a difficult position. It turns out that his girlfriend and her brother, neither of whom know his real name or occupation, and involved in the drug trade, headed by Charles S. Dutton's character Shell. As Ty gets closer to Shell, his facade slowly breaks down until the end when his girlfriend is sent of of town and her brother dead.
Score: 8.7/10