Not surprisingly, Shark is back for a second season, premiering tonight on CBS, 10 PM, ET/PT. While it wasn’t a runaway hit in its first season, the James Woods vehicle consistently garnered good numbers in its Thursday night slot, good enough that CBS feels confident enough to move it to a more competitive Sunday night front.

If tonight’s episode is any indication, the sophomore season of Shark is going to take a darker turn. The witty courtroom shenanigans of Sebastian Stark (Woods) and his prosecutorial team take a backseat to gritty investigative work. In “Gangster Movies,” new characters are introduced, characters from last season are reinvented and the series as a whole dives more deeply into crime at its root.

Of course, this requires a revamping of the series. At the end of last season, DA Jessica Devlin (Jeri Ryan) was defeated in her reelection bid by Leo Cutler (Kevin Pollack). This season finds her joining Sebastian’s team, creating a new dynamic between the two characters. Pollack, who’s no stranger to playing smarmy characters, looks to be the foil to Sebastian and Jessica in his role as the newly elected bureaucratic DA.

Another character, Danny Reyes (Kevin Alejandro) is introduced in this episode. His is a personality shrouded in a mysterious past, a veteran of the DA office’s organized crime unit, who tentatively joins Sebastian’s team in hopes of bringing down a Russian mob kingpin.

As convoluted as all this might sound, the premiere episode ties it all together seamlessly. After the prosecution’s sole witness in a double homicide is killed by a bus bomb, evidence points to a more insidious threat. To their credit, the producers veered away from terrorist plots, and went with an organized crime angle. Art dealer Andre Zitofsky (Arnold Vosllo, The Mummy) spends his hours as a new breed of Russian mob boss. Proving he’s behind the killings proves to be a daunting task, however.

With “Gangster Movies,” Shark moves away from procedural courtroom drama into the uncharted territory of action crime fiction. It’s a good way to start a new season. If the series can maintain the wit of its first season while infusing it with a more action-oriented sub-plot, Shark may well be a force to be reckoned with on Sundays.