NC Gubernatorial Debate (7pm) - Tonight's debate will air live on WRAL, UNC-TV and C-SPAN2.

Arrow (8pm, CW) - Assassin Deadshot kills one of Oliver's targets and then sets his sights on gunning down Walter. To stop him, Oliver enlists the help of Det. Lance, but his plan leads to dire consequences.

Nature: Magic of the Snowy Owl (8pm, UNC-TV) - Chronicling the efforts of a pair of snowy owls to raise their young during the 82-day summer season in the Arctic. When the father owl is forced to travel farther than normal to find food, the owls move their nest, embarking on an odyssey that takes them across a river, which forces the young owlets to swim. This better not have a sad ending.

Modern Family (9pm, ABC) - When the Dunphys' neighbors find Claire's annual Halloween extravaganza inappropriate, Phil suggests having an open house for the holiday. Meanwhile, Mitchell and Cameron host a costume party, but must also field questions from Lily about her birth mom.

The Houstons: On Our Own (9pm, Lifetime) - In the opener of this new series following Whitney Houston's family in the aftermath of the singer's death, the family comes together for Mother's Day. In a 9:30 episode, Pat becomes concerned about Bobbi Kristina's choices and the amount of time she's spending with Nick. Adrienne reviews.

Nashville (10pm, ABC) - Rayna focuses on her family and discovers the depth of the financial problems she and Teddy face, while Juliette tries to tempt Deacon with a contract offer. Also, Juliette's mom comes back into her life.

American Horror Story: Asylum (10pm, FX) - An exorcist visits Briarcliff to help a troubled boy, and Sister Jude reveals a disturbing secret.

Chicago Fire (10pm, NBC) - Casey faces pressure to cover for a cop's son, who was responsible for a drunken-driving accident that left a teenager paralyzed. Meanwhile, Severide ignores his doctor's warnings that his neck injury may never heal if he doesn't seek treatment.