‘24’ scores even if Chicago doesn’t

Jack Bauer may or may not save the world, but Kiefer Sutherland’s secret agent is already doing his part to buck up Fox’s midseason. Sunday’s season premiere of “24” was the drama’s most-watched episode ever, with an average of 17 million viewers, according to early data from Nielsen Media Research.

The debut was undoubtedly helped in many markets by an NFL playoff between Carolina and Chicago that ran long. But a special second episode of “24,” airing right after the first hour, also scored well, with 15.5 million viewers.

Fox’s good fortune spelled trouble for its network rivals. NBC’s “The West Wing” sank to record lows in total viewers (6.4 million) and in the key demographic of adults aged 18 to 49.