From its enigmatic and unsatisfying title to its shifting tone, “The Unusuals” (9 p.m., ABC) throws viewers a series of curveballs. Is it a quirky police comedy? A gritty, shot-on-location drama? A supernatural mystery that just happens to be set in a precinct house? Or a slow-building love story?

Closer to “Barney Miller” than “The Shield,” “The Unusuals” has almost as many personalities as it has ensemble characters, and there are at least eight of them. And none of these folks is exactly what he or she seems.

We first encounter Detective Casey Shraeger (Amber Tamblyn) working vice in come-hither attire. Her awkward task is hampered by her intrusive mother’s phone calls. We can tell from Mom’s accent and attitude (“you can’t get good help these days”) that Casey does not hail from a blue-collar background.

She’s quickly assigned to a homicide unit that has just suffered the loss of one of its own — a thuggish, corrupt cop shown only in photographs. At first glance, his former partner, Detective James Walsh (Jeremy Renner), appears to share his talent for bending rules and breaking laws. But, like I said, he has his secrets, including a faded baseball card with his picture on it.

Adam Goldberg stars as he always does, as the quick-to-anger office neurotic. But in this case, he’s a cop with a medical secret that gives him a peculiar death wish. Across the desk sits Detective Leo Banks (Harold Perrineau), a superstitious officer scared to death of dying at age 42. Don’t ask.

The precinct also has a vain brown-noser who refers to himself in the third person.

The characters are complicated enough to maintain our interest. I’m just not sure that viewers will sit still for the show’s serious mood disorder. And has ABC learned nothing from “Life on Mars”? If you want to launch a New York cop show, why do it opposite the popular “CSI: NY” and “Law & Order,” the granddaddy of them all?

• “American Masters” (8 p.m., PBS, check local listings) presents “Glass: A Portrait of Philip Glass in Twelve Parts,” a profile of the composer of challenging operas and symphonies who has gained his widest audience with film scores.

Trained in Paris by Nadia Boulanger and later instructed by Indian master Ravi Shankar, Glass went on to fuse Eastern and Western musical traditions in his own particular style. And this made him one of the most revered and reviled composers of his time.

This “Masters” is a lot like Glass’ work. It’s captivating yet repetitive, profound but a bit indulgent, and, in the end, at least twice as long as you can endure.

Tonight’s other highlights

• A building collapse becomes a burial ground for vital evidence on “Lie to Me” (7 p.m., Fox).

• Crews pursues Reese on “Life” (8 p.m., NBC).

• Exit, stage right on “American Idol” (8 p.m., Fox).

• Ben wants a date with the Smoke Monster on “Lost” (8 p.m., ABC).

• “Mythbusters” (8 p.m., Discovery) returns with a two-hour demolition derby.

• Murder stages a dress rehearsal on “CSI: NY” (9 p.m., CBS).

Cult choice

A Brooklyn boy runs away from home and hides out in Coney Island in the wonderfully different 1953 low-budget comedy “Little Fugitive” (7 p.m., TCM), directed by Morris Engel, the subject of a nightlong tribute.