Fans who can’t wait until Sunday for the third season premiere of “Downton Abbey” can visit the Abbey itself on “Castles on Camera: Royal Residences on TV” (8 p.m., HGTV).

The “Abbey” is really Highclere Castle, home of the Carnarvon family since 1679. Other venerable domiciles featured here include Althorp, home of the Spencer family and where the late Princess Diana is buried. “Castles” visits Cliveden House in the English countryside, built in 1666. In the first half of the 20th century it was the home of the Astors, who entertained lavishly.

Cliveden House gained a notorious reputation in the late 1930s as a gathering place for British aristocrats eager to appease Adolf Hitler and even bring his Nazi policies to Britain. They were known as the Cliveden Set. These sensibilities were touched upon on the recent incarnation of “Upstairs Downstairs” on PBS. There’s no telling if “Downton Abbey” will stick around long enough to get us to the late 1930s.

Tonight’s other highlights:

• Scheduled on a two-hour “Dateline NBC” (8 p.m.): Two suspects confess to a Nevada teen’s murder.

• The Sharks compete for an investment opportunity with an entrepreneur who threatens to revolutionize the art of face painting on “Shark Tank” (8 p.m., ABC).

• “Great Performances” (8 p.m., PBS) presents “Paul Simon’s Graceland Journey.”

• Two murders have a peculiar weapon in common on “CSI: NY” (8 p.m., CBS).

• After becoming a castaway, a spoiled heir returns home with new insights and powers on the pilot episode of “Arrow” (8 p.m., CW).

• “Taste in Translation” (8 p.m., Cooking) looks at five different birthday dishes from around the globe.

• Highways become a killer’s hunting ground on “Blue Bloods” (9 p.m., CBS).

• “Merlin” (9 p.m., Syfy) enters its fifth and final season.

• “Bering Sea Gold” (9 p.m., Discovery) dredges up a new season.

• Designers renovate bars all over the city that made beer famous on “Made in Milwaukee” (10 p.m., DIY).

• Remarkable set design and Cold War paranoia are the real stars of the 1957 shocker “The Incredible Shrinking Man” (10 p.m., TCM).