TV tonight: 'S.H.I.E.L.D.,' 'Playing House'

Agents of S.H.I.E.L.D. | ABC, 8 ET/PT

Coulson gets another Avengers visitor, Cobie Smulders' Agent Maria Hill, who may help him discover what viewers already know: Ward is a traitor. Whether Ward's treachery can be reconciled with all that came before is a question best left to the show's most devoted fans, but it has, at least, made the character a bit more interesting.

Pioneers of Television | PBS, 8 ET/PT (times may vary)

This examination of TV's treatment of racial and ethnic minorities features interviews with two true pioneers: Diahann Carroll and Bill Cosby. Unfortunately, anyone who thinks the battles they fought are over need only check the sports headlines or the current TV schedule: There's not a single broadcast comedy built around an African-American performer, and only one (The Mindy Project) led by any ethnic minority.

Playing House | USA, 10 ET/PT

Lennon Parham and Jessica St. Clair, who starred in and created the short-lived NBC sitcom Best Friends Forever, go the same route with a similar series for USA. Self-indulgence remains a problem. (Parham and St. Clair sometimes seem to think amusing each other is enough. It isn't.) But their latest effort is funnier, less smug, and has a stronger supporting cast (led by Keegan-Michael Key and Zach Woods tonight, with Jane Kaczmarek arriving later). The result is a more pleasant, if still not essential, half-hour.