“Nash Bridges” is coming back with original star Don Johnson. There’ll be a two-hour special on the USA Network, and if it does well enough, a series will follow. The original ran on CBS for six seasons, from 1996 to 2001. In case you’re wondering, Nash is still running San Francisco’s Special Investigation Unit; but while the world has changed, he hasn’t. There’s no word if Cheech Marin or anyone else from the original cast is coming back.