Brash young working-class guys from a New York outer borough decamp for the sunny beaches and glitzy nightclubs of Miami in the new prime time soap opera “South Beach” (7 p.m., UPN).

But not everything in Miami involves sunscreen and disco balls. The guys, Matt (Marcus Coloma) and Vincent (Chris Johnson), get involved in some of the heavier aspects of security work at a hotel named the Soleil, owned by the beautiful Elizabeth Bauer (Vanessa Williams, in Joan Collins mode). Giancarlo Esposito stars as a shady entrepreneur. In between bouts of business, both legitimate and not so nice, “South Beach” will provide plenty of glances at the resort city’s music and modeling scenes. Note: A review copy was not made available in time for this column.

¢ Immature viewers of all ages can rejoice as “Mythbusters” (8 p.m., Discovery) enters a brand new season. For the uninitiated, this show tests urban legends and common assumptions with good old-fashioned laboratory know-how. Do “corked” baseball bats provide hitters with an advantage? Do alligators breed in city sewers? Are commercial passenger planes hotbeds of contagion?

In tonight’s episode, hosts Jamie Hyneman and Adam Savage test the “legend” that a prisoner devised a crossbow out of newspapers, a cafeteria tray and the elastic in his underwear and used it to kill a fellow inmate.

Along the way, their helpers put other urban legends to the test. Does vodka really work as a mouthwash? Will it take the smoky smell out of your clothes? Will it fend off a bee attack? You’ll just have to tune in for further “proof.”

¢ On two episodes of “Lost” (ABC), the crash and its aftermath from both sides now (7 p.m.), Charlie’s secret (8 p.m.). Although the first features clips of past action, these are the first new “Lost” episodes in a long time. Enjoy.

Tonight’s other highlights

¢ JT discovers a plague plant in Holland on “E-Ring” (7 p.m., NBC).

¢ Jackie’s mortification on “That ’70s Show” (7 p.m., Fox).

¢ Suspicion falls on respectable people on “Criminal Minds” (8 p.m., CBS).

¢ The expense of spirit in a waist of shame on “The Biggest Loser: Special Edition” (8 p.m., NBC).

¢ A dancer takes flight on “CSI: NY” (9 p.m., CBS).

¢ Vigilante justice runs amok on “Law & Order” (9 p.m., NBC).

¢ Russell asks Mariel to explain herself on “Invasion” (9 p.m., ABC).