HDTV Listings for April 21, 2010

What we're watching tonight:

• CBS (1080i) brings The New Adventures of Old Christine at 8 p.m., and the season finale of Accidentally on Purpose at 8:30 p.m.

• Fox (720p) has American Idol at 9 p.m.

• NBC (1080i) airs Mercy at 8 p.m. and Law & Order: SVU at 10 p.m.

• CW (1090i) has Fly Girls at 9 p.m. and High Society at 9:30 p.m.

• Discovery (1080i) has the season premiere of Weird or What? at 8 p.m. and What a Tool at 10 p.m.

• History (720p) has Gangland at 9 p.m.

• DirecTV (1080i) has Underbelly at 10 p.m.

• USA (1080i) has In Plain Sight at 10 p.m.

• Spike (1080i) has The Ultimate Fighter at 10 p.m.

• Comedy Central (1080i) has South Park at 10 p.m. and Ugly Americans at 10:30 p.m.

• TBS (1080i) airs House of Payne at 10 & 10:30 p.m.

• A&E (720p) has Dog the Bounty Hunter at 10 p.m. and Billy the Exterminator at 10:30 p.m.

• Showtime (1080i) has Inside NASCAR at 10 p.m.

• Syfy (1080i) has Ghost Hunters at 9 p.m. and the season finale of Destination Truth at 10 p.m.

• ESPN (720p) has Phillies/Braves baseball at 7 p.m.

• TNT (1080i) has NBA playoffs action with Bobcats/Magic at 7 p.m. and Spurs/Mavericks at 9:30 p.m.

• Versus (1080i) has NHL playoffs action with Capitals/Canadiens and Sabres/Bruins at 7 p.m., and Canucks/Kings at 10 p.m.