TV tonight: 'Last Resort,' 'Big Bang Theory'

• 'Last Resort' is looking up; set your DVRs accordingly
• Buzz Aldrin drops by 'Big Bang Theory'
• Lucy Lawless visits 'Parks and Recreation'

Last Resort
ABC, 8 ET/PT

In these early days of its run, this well-cast ABC adventure seems to be settling into a pattern: The episodes work well when we're on the submarine, less so on the island, and dangerously less so in Washington. The good news is that tonight's tense outing, built around Marcus and Sam's negotiations with our treacherous government, spends much of its time on the sub while boasting a better-than-average island plot, albeit one that over-indulges in the show's fondness for grand gestures. There's even a welcome sign at the very end that the D.C. story could be improving. So if you've been debating dropping the series from your DVR, tonight's hour might win it a reprieve.

The Big Bang Theory
CBS, 8 ET/PT

He blinded her with science. In danger of losing Penny, Leonard finds that a little scientific knowledge can lead to romantic power — and thank goodness for that, because it would be nice to see this on-again, off-again relationship stay on for a while. But love in bloom isn't the only draw: Tonight's outing kicks off the November sweeps with a cameo by Buzz Aldrin, who's about as ideal a Big Bang cameo as you can imagine.

Parks and Recreation
NBC, 9:30 ET/PT

Tonight brings bad relationship news to Leslie, but good news to viewers: The almost always entertaining Lucy Lawless returns as Diane, as Ron and Andy take her and her two girls out trick-or-treating. Alas, if you were hoping the girls would go as Xena and Lucretia, the trailer indicates that you will be disappointed.