“Nova” (7 p.m., PBS, check local listings) interrupts your trick-or-treating fun for something truly terrifying. “Monster of the Milky Way” presents interviews with scientists concerned that a massive black hole lurks in our own galaxy. There goes the neighborhood. “Monster” uses computer graphics to explain the mysteries of black holes and presents a terrifying glance at what it might be like to fall into its gaping galactic maw.

¢ Silly and supernatural holiday fare includes a celebrity seance on “Chriss Angel Mindfreak” (9 p.m., A&E). The illusionist holds hands and contacts the other side in the company of Steve Valentine, singer Deborah Gibson and the musical group Three 6 Mafia.

¢ The paranormal plumbers known as the “Ghost Hunters” (10 p.m., Sci Fi) will present a six-hour live investigation of the Stanley Hotel in Estes Park, Colo., best known as the site where Stephen King wrote “The Shining.”

¢ “Late Night with Conan O’Brien” (11:35 p.m., NBC) will feature an all-skeleton episode. “This may be the finest hour of television NBC has ever produced – with skeletons,” quips O’Brien.

The show is a complete re-creation of an episode of “Late Night” from May 2006. From the monologue to the comedy sketches and guests, no living humans will be featured in the show – just skeletons. Guests making their bones tonight include Larry King, Omar Epps (“House”) and actress and pole-dancing workout instructor Sheila Kelley.

¢ From “Spinal Tap” to “The Office,” fake documentaries have been the most provocative form of comedy. But their success has made it difficult to look at real documentaries about offbeat subjects without the feeling that you’re being spoofed. The “Independent Lens” (9 p.m., PBS, check local listings) presentation “Muskrat Lovely” chronicles the annual “Miss Outdoors” pageant in a small Maryland county on the Chesapeake Bay.

The beauty contest, now in its 50th year, is part of a greater commemoration of the muskrat-hunting season, complete with competitions in muskrat trapping, goose calling, log sawing and, most prized of all, muskrat skinning.

For all of its quirkiness, “Muskrat” presents an often affectionate and even reverent view of a tight-knit community and its unique traditions.

Tonight’s other highlights

¢ A team savior proves anything but on “Friday Night Lights” (7 p.m., NBC).

¢ “Exorcism: Driving Out the Devil” (7 p.m., History) looks at legends of demonic possession and practices and rituals that have sprung up as a result.

¢ An unexpected reunion on “The Unit” (8 p.m., CBS).

¢ A murder from Halloween night 1992 deserves re-examination on “Law & Order: Criminal Intent” (8 p.m., NBC). Liza Minnelli guest stars.

¢ After a mugging, a married couple fight for their lives on “House” (8 p.m., Fox).

¢ Halloween robbers nab an expensive keepsake on “Veronica Mars” (8 p.m., CW).

¢ Benson feels conflicted on “Law & Order: Special Victims Unit” (9 p.m., NBC).

¢ Halloween brings anxiety on “Boston Legal” (9 p.m., ABC).