Timothy Olyphant in 'Justified' and Michael C. Hall in 'Dexter'
FX/Showtime Timothy Olyphant in 'Justified' and Michael C. Hall in 'Dexter'

Tonight, the FX drama "Justified" finishes its third season, which has placed US Marshall Raylan Givens (Timothy Olyphant) against the likes of Kentucky’s most dangerous (and often insane) criminals. "Justified," which was created by Graham Yost and based on an Elmore Leonard character, has continually evolved from a standard crime show. Over its three seasons, it's become one of the most critically applauded dramas on television. This might make you think about another show that shares the same DNA, "Dexter," which started in a similar place before becoming a critical whipping boy over the last six years.

"Dexter," thanks to Showtime, is more graphic, but the two shows carry much of the same blood. They're both crime dramas centered on antiheroes who toe the line between ethical and moral decisions -- though one is a serial killer and the other is a trigger-happy law enforcement agent. And yet, around its third season, critics started getting tired of "Dexter." When reviewing the fourth season, Maureen Ryan claimed the show "is one journey that feels as though it has dragged on too long."

What has Yost done to avoid to avoid falling into the same trap, and what should he and the show continue to do? Here’s a rundown of what has made "Justified" continue to work, and what “Dexter” can learn from it:

Margo Martindale in season two of 'Justified'
Prashant Gupta/FX Margo Martindale in season two of 'Justified'
Don’t Create a Formula

The most pressing issue with the latter seasons of "Dexter" has been its continual repetition. Dexter (Michael C. Hall) finds someone who, like him, is a killer. The two come close to one other, and then Dexter must eliminate that person by the end of the season, thus resetting the status quo.

Meanwhile, "Justified" has put together three very different seasons when considering their narrative structures. The first used a serialized format similar to other procedurals out there, while the two that followed have centered more on season-long arcs. But while season two focused on Raylan's battles with a Harlan Country matriarch, the marshall has been a bit player for much of season three as the show's to focus on the battles between the different criminals. I never know what to expect when going into an episode of “Justified,” and that's one of its best qualities.

Don’t Pigeonhole Characters

Part of the great backstory of "Justified" is that Walter Goggins, who plays Boyd Crowder, was only meant to appear in the pilot. But Goggins made the character so compelling he's now a series mainstay. Better yet, Boyd has gone from demolition expert to religious preacher to security for a coal company to, now, a gang leader. Others, like Ava Crowder and Raylan’s father, have gone through similar changes.

Compare these secondary characters to Batista and Masuka on “Dexter.” We know exactly who they are, and they fill the same roles every year on the series even if their title in the office changes. “Justified” knows that just because a character acts one way for a season, they don’t have to come back the same way for the next.