Watch it

“Portlandia” (7:30 and 11:04 p.m., IFC). The mayor (Kyle MacLachlan)  disappears, and Fred and Carrie have to find him. And other weird stuff happens.

“Who Do You Think You Are?” (8 p.m. NBC). Country singer Tim McGraw traces his ancestry. . . . and discovers his father was a famous closer for the Phillies! Oh, and George Washington is way down the family tree too.

“Fringe” (9 p.m., Fox). We jump back to the alternate universe, where Broyles is missing (and very dead) and the team investigates flesh-eating insects unleashed by a bioterrorist. Should be interesting.

“Spartacus: Gods of the Arena” (10 p.m., Starz). The House of Batiatus is divided by the rift between father and son, and Lucretia gives her hubby the green light to carry out a risky scheme. Hmmm, I smell patricide . . . .

Record it

“Ricky Gervais Show” (9 p.m., HBO). It’s all about Karl (isn’t is always?), including his encounters with insects and random diary entries.

Skip it

“Kitchen Nightmares” (8 p.m., Fox). Gordon Ramsay checks back with restaurants he’s helped to see if they’re continuing to follow his advice. I can tell you right now: Of course they’re not.