“In Plain Sight” (9 p.m., USA) returns for a third season as Mary Shannon (Mary McCormack) recuperates from a bullet wound and struggles to remember her assailant.

For the uninitiated, “Plain” follows FBI agents who monitor criminals and witnesses given new identities and placed under federal protection in the Desert Southwest. Despite its sun-blasted locale, “Plain” is decidedly darker than other USA fare, such as “Psych,” “White Collar,” “Burn Notice” and “Royal Pains.” Misanthropic Mary sets the tone, chattering almost nonstop about how much she would rather be left alone. This doesn’t stop her from embarking on a new case almost the minute she leaves the hospital.

Look for guest star Donnie Wahlberg, a transplanted Boston burglar turned struggling diner owner who falls under suspicion when local criminal activity seems remarkably similar to his old line of work. Other recurring guest stars include Lesley Ann Warren as Mary’s mother. Allison Janney, Steven Weber, Rita Moreno, Tess Harper and Josh Cooke are also slated to appear this season.

• “American Masters” (8 p.m., PBS, check local listings) presents “I.M. Pei: Building China Modern.” It’s well-known that China’s economic growth has resulted in a building boom of epic proportions. Many of its cities have become unrecognizably overbuilt, featuring an undistinguished architectural style.

To date, the ancient city of Suzhou has been spared and still resembles a Ming Dynasty Amsterdam, a city defined by water and canals filled with venerable homes made of wood and tile.

To design a modern museum in Suzhou, Chinese authorities turned to the famous Chinese-born American architect I.M. Pei, whose family has roots in Suzhou stretching back 600 years.

“Building” offers a glance at Pei and his achievements as the 84-year-old architect approaches what might be his final task. It also looks at the difficulties of balancing a respect for the ancient with the demands of a society modernizing at a frenetic gallop. It makes much of Pei’s delicate task of negotiating artistic nuances with Chinese authorities. But “Building” is best appreciated as documentary trip to a beautiful city and its struggle to survive the onrush of history.

Tonight’s other highlights

• Way up north to Alaska on “Human Target” (7 p.m., Fox).

• Linus evangelizes his peculiar holiday beliefs in the 1974 animated special “It’s the Easter Beagle, Charlie Brown” (7 p.m., ABC).

• Greedy developers inspire young environmental activists in the 2006 comedy “Hoot” (7 p.m., Disney), an adaptation of a young-adult novel by Carl Hiaasen.

• On two episodes of “Law & Order: Special Victims Unit” (NBC), a killer targets immigrants (8 p.m.), a murder mirrors a 30-year-old case (9 p.m.).

• Usher performs on the “American Idol” (8 p.m., Fox) results show.

• The search for a perfect birthday gift on “Modern Family” (8 p.m., ABC).

• Mandy follows her heart to New York on “Fly Girls” (8:30 p.m., CW), where it is promptly stomped on.

• London-bound on “Ugly Betty” (9 p.m., ABC).

• Money is no object in Dr. Tom’s parallel world on “Being Erica” (9 p.m., SoapNet).