Amy Poehler is a small-town official in Parks and Recreation on Thursday over NBC.

Three new shows are introduced to the airways this week.

For a humorous side to homicide, The Unusuals premieres Wednesday at 10 p.m. on ABC (Ch. 5, 6).

Basic story: Detective Casey Shraeger (Amber Tamblyn) is walking the streets of New York as an undercover hooker when she’s whisked away for a new assignment in the homicide division.

She’s paired with Detective Jason Walsh (Jeremy Renner), whose partner was murdered the night before. She joins NYPD’s Second Precinct, where the eccentricities of her colleagues begin to unfold: one detective (Harold Perrineau) always wears his bulletproof vest; his partner (Adam Goldberg) has started taking dangerously crazy risks; and another (Kai Lennox) talks about himself in the third person as he shamelessly self-promotes. Everybody in the department has secrets, it seems — including newbie Casey, and the murdered cop.

What you’ll love: The characters are quirky and quick to quip — everything is fair game. And voice-overs from the dispatcher add additional light moments, such as: “Be on the lookout for a man in a hot-dog costume last seen running west on Houston Street. Suspect may or may not be wielding a samurai sword.”

Southland is liked to L.A. Law, but from a cop’s perspective.

The show premieres Thursday at 10 p.m. on NBC (Ch. 7, 10).

Basic story: Sunny California this ain’t. The streets of Los Angeles take on a decidedly darker hue in this new crime drama that follows a group of detectives and patrol officers on and off the job.

Our window into this world is rookie cop Ben Sherman (Ben McKenzie), who quickly learns how disturbing the work can be. His training officer is the decidedly more jaded John Cooper (Michael Cudlitz). Rounding out the cast as detectives are Kevin Alejandro, Shawn Hatosy, Regina King, Michael McGrady and Tom Everett Scott. Arija Bareikis plays a patrol officer hoping to be the first woman to join the SWAT team.

Greg Daniels and Michael Schur think small-city government can be hilarious, and they’ll try to prove it with Parks and Recreation which begins Thursday on NBC (Ch. 7, 10).

Shot in The Office-style mock-documentary form, their sitcom stars Amy Poehler as Leslie Knope, an ambitious, ever-optimistic bureaucrat in the fictional community of Pawnee, Ind. She works with a brick wall of a boss who thinks government is a waste of money, a city planner she likes, an ambitious colleague and a clueless intern.

Basic story: The main story line finds Leslie trying to help a local nurse turn an abandoned pit into a city park, but Daniels said the show really is about “the anarchy of low-level democracy and how hard it is to get stuff accomplished.”

Before delving into this world, Daniels and Schur did their research. They scoured newspapers, watched various city council meetings on the Web and talked to government officials who told stories about parks that took decades to build.

“We assumed, like many people do, that the primary reason things take a long time is bureaucracy and red tape — and there’s a bit of that,” Schur said. “But if you ask 100 people what to do with [a parcel of land], they’ll have 100 different ideas.”

“That’s one of the themes of the show,” Daniels added. “How do you get something decided when everybody has a vote and nobody reports to anybody?”