The solid cable drama “The Shield,” (9 p.m., FX) ends its first season with the precinct house reeling from a race riot and Det. Vic Mackey (Michael Chiklis) still straddling the thin line between corruption and outright evil. Tonight, Vic makes a deal with his former nemesis, Capt. Aceveda (Benito Martinez), after he learns that Assistant Chief Gilroy has been trying to implicate him in the murder of a gang member.

Vic Mackey has clearly replaced “NYPD Blue’s” Andy Sipowicz as primetime’s most intense and troubled police officer. With his cruel blue eyes, manic gum-chewing and bulging biceps, Chiklis projects an aura of nervous, calculating menace. After an impressive start, “The Shield” could still use some improvements. The dialogue occasionally bogs down in predictable precinct-speak. And few of the characters have developed fully three-dimensional personalities or domestic lives. Mackey’s concern for his autistic son’s education has given him and his infrequently seen wife something to do together, but for the most part, he’s all work, all the time. And after tonight, that may cost Vic more than he could imagine.

After last night’s “preview,” the candid-camera gag show “Spy TV,” (7 p.m., and 7:30 p.m., NBC) officially enters its second season. NBC is hoping that viewers of this practical joke-athon will watch pretty former beauty queen and actress Ali Landry as the hostess. Landry appears before a hyped-up studio audience and introduces the taped shenanigans. Tonight’s set-ups include a billboard that squirts liquid on passers-by and a smoking pay phone.

ABC has made this the summer of the documentary. After spending four hours in the Hamptons, the network launches “Boston 24/7,” (9 p.m.) a six-part cinema verite look at the workings of the Boston city government, from the office of a politically embattled mayor to a cop on the beat. Three months in the making, tonight’s “Boston” covers a detective’s efforts to find the killer of a popular community leader and the embattled mayoral press secretary’s dealings with increasingly testy reporters.

“Biography: Eureka!” (7 p.m., A&E) profiles the 20th century’s most influential inventors, including the famous (Thomas Edison, the light bulb, phonograph and motion pictures) and some who may not be so familiar, including Gordon Gould (the laser) and Leo Baekeland (plastics).

Tonight’s other highlights

“Scientific American Frontiers,” (7 p.m., PBS, check local listings) casts a skeptical eye on alternative medicines, including acupuncture, herbal remedies, chiropractors and therapeutic “touch” treatments.

Games and elimination on back-to-back installments of “The Mole 2: The Next Betrayal,” (7 p.m. and 8 p.m., ABC).

Scheduled on “Dateline,” (9 p.m., NBC): two brothers develop a high tech cure for blindness.