Merlin

True Blood
9 pm/ET HBO
How much of a relief was it to know that Lafayette isn't dead? Of course, being chained up in a vampire's basement and watching another human get eaten alive isn't much of an alternative, but you can't have everything. And even though he hasn't been to work for a while, Lafayette probably wouldn't recognize Merlotte's if he came back tonight, especially after Maryann works the bar's usual customers into a frenzy that Sam isn't likely to forget. — Joe Friedrich

Merlin
8 pm/ET NBC
This UK import's enchanting take on the Arthurian fable casts a gentle spell as it spins the story of the teenage warlock Merlin (Colin Morgan) and his arrival in the kingdom of Camelot, where he finds a mentor in the kindly court physician (Richard Wilson). It's far from a magical place — the current king (Anthony Head) has banned all spells and Prince Arthur (Bradley James) is something of a bully. A second episode, about a snake-like Knight Valiant attempting to cheat his way to victory in Camelot's annual sword tournament, follows the series premiere. — Jeff Gemmill

Impact
9 pm/ET ABC
Uh-oh, it's summer again, time for cataclysmic mayhem to threaten us all. This time, a dead star strikes the moon, knocking it out of its orbit and sending it... guess where? Out to save Earth (until NBC sends a meteor our way next month, at any rate) are scientists Alex Kittner (David James Elliott), a widower with two cute kids and a grumpy father-in-law (James Cromwell), and Maddie Reese (Natasha Henstridge), who's conveniently divorced. This two-parter concludes next Sunday. — Paul Droesch

In Plain Sight
10 pm/ET USA
The Shannon ladies have always had a knack for getting into trouble, especially the kind they bring on themselves. But this time around, it's the strange vendetta of Agent O'Connor (played by Mary McCormack's real-life brother Will McCormack) that has landed Brandi in hot water. Charged with murder and drug trafficking, Brandi must rely on Mary to get her off the hook and to put the pressure on O'Connor to abandon his quest to put Brandi behind bars. — Brie Hearn

Killer Hair
8 pm/ET Lifetime Movie Network
Based on one of Ellen Byerrum's Crime of Fashion books, this lighthearted murder mystery stars Maggie Lawson as Lacey Smithsonian, a fashion columnist who finds herself in the middle of a killing spree that police refuse to acknowledge. When Lacey's eye for fashion spots overlooked clues, she gets a front-page story that also puts her in the killer's sights. A smidge of intrigue and a stellar supporting cast, including Finola Hughes, Mario Cantone and Mary McDonnell, help make this stylish whodunit great escapist fare. — Rhoda Charles