Based on stories by Elmore Leonard, “Justified” captures his darkly funny, morally murky tone and spikes the traditional crime procedural with hooch and Oxycontin, tracking its hero’s attempts to thwart colorful drug dealers and gunrunners and negotiate his own fractured relationships. The series unspools in an oddly captivating alternate South peopled by whimsically twisted archetypes and marked by sudden shifts between folksy black comedy and graphic violence. (The thug in the premiere is known as the Ice Pick.)

Last year the series won a Peabody Award, and its second season was among the most lauded of 2011, netting four Emmy nominations, including a first for Mr. Olyphant and a supporting actress win for Margo Martindale, who played a crime matriarch. Ratings for Season 2 increased 15 percent in total viewers, and an average of just under 2.2 million watch each new episode on Tuesday nights, an audience that grows to nearly 4 million each week when it includes DVR viewers, though they still lag behind those of FX dramas like “Sons of Anarchy” and “American Horror Story.” The challenge for the show’s producers is to build on the series’s momentum from last season and transform from critical favorite into critically acclaimed hit.

“It’s coming off one of the best seasons any series put forth last year, and that’s a really tough act to follow,” said John Landgraf, the president of FX. “But when you have a virtually ideal central character and central performance, audiences are going to find it.”

As the face of the series Mr. Olyphant has perhaps the most impact on whether the show will continue to succeed. By all accounts it’s a job he takes most seriously, playing an active role behind the scenes as well. Mr. Leonard himself calls the actor’s performance the best screen adaptation ever of a Leonard hero, a category that includes names like George Clooney and John Travolta.

“He played Raylan exactly like I heard him when I was writing him,” said Mr. Leonard, an executive producer of the series. (“Raylan,” a new novel by Mr. Leonard about the character, comes out on Jan. 17 as well.)