FOX KEEPS VIEWERS ON EDGE OF THEIR SEATS.

Byline: David Kronke Television Critic

Give Fox credit -- it's really carved out a niche for itself with its Monday lineup of overheated, paranoid serialized thrillers. ``24'' and ``Prison Break'' established the brand, featuring desperate, violent men confronting, among other things, a corrupt shadow government.

Part of the appeal of these series is they move at such a breathless pace that they addict both those able to discern their narrative implausibilities and those just happy to be along for the ride. Add to the mix ``Vanished,'' which could be the most nuanced -- or simply the most convoluted -- of the bunch.

``Vanished'' takes as its starting point the mysterious disappearance of Sara Collins (Joanne Kelly), the crusading wife of a Georgia senator (John Allen Nelson), at a fundraiser in her honor.

Graham Kelton (Gale Harold), a disgraced FBI agent, is assigned the case. (NBC's similar, upcoming ``Kidnapped'' also features a crack investigator haunted by a previous case, but here's where Fox differs from the other networks: Where NBC leaves the fate of the missing child from the earlier investigation ambiguous, Fox's show ruthlessly kills off the kid Kelton sought to rescue, making the guy exponentially more haunted.)

Everyone's a suspect: ``My wife and I love each other,'' the senator fairly sneers to Kelton; the politician's children from a previous marriage carry baggage of their own. The story is pursued by a TV news reporter (Rebecca Gayheart) who is so ravenous for success that she sleeps with her cameraman while cable news plays out on a nearby TV.

Tonight's episode piles on the complications at a furious pace. Oblique tattoos are applied to conspirators only after they've been murdered. A body, missing 10 years, turns up, virtually fully preserved. And Sara Collins, it turns out, has so many mysteries swirling around her that she may not even be Sara Collins.

If ``Vanished'' can keep up this level of manic plot development without getting too derailed, it could reasonably become a feature performer in Fox's Mayhem Mondays. Unfortunately, there are a few casting choices that lack the requisite gravitas or charisma or, simply, the credibility their roles require.

More worrisome, the producers didn't provide a second episode for review, which isn't a good sign, particularly since ``Prison Break's'' producers managed to send two episodes, even though that show has already established itself.

As ``Prison Break's'' second season commences tonight, the Fox River Eight (as the fugitives are quickly dubbed) have escaped, but still find themselves landlocked dangerously near the prison. The feds, led by Agent Mahone (a well-cast William Fichtner, propitiously freed from the Florida swamps of ``Invasion''), are in feverish pursuit -- Mahone is coming tantalizingly close to unlocking the mysteries behind those tattoos Michael Scofield (Wentworth Miller), mastermind of the breakout, employed to facilitate his daring getaway.

Last season, Michael's half-brother Lincoln (Dominic Purcell) was framed for murdering the vice president's brother. While that mystery came oh-so-close to resolution last season, as usual for programs of this nature, it's always one step forward, two steps back. In other words, the body count proceeds apace tonight.

Of course, plotting tilts toward suspension-of-disbelief-land, as Lincoln, newly freed from death row, in episode two places himself in harm's way. But ``Prison Break's'' producers manage to maintain the claustrophobia of the first season, as their protagonists find themselves in an outside world they can't trust for even a second, and the stakes are raised to incandescent levels.

David Kronke, [phone]

david.kronke(at)dailynews.com

VANISHED - Three stars

What: A senator's wife's disappearance triggers what is billed as a ``Da Vinci Code''-style conspiracy.

Where: Fox (Channel 11).

When: 9 tonight.

In a nutshell: A nice setup, but one presumes that if the follow-through were as nice, Fox would've provided more episodes for review.

PRISON BREAK - Three and one half stars

What: As the second season begins, the inmates are now on the lam, seeking either justice or vengeance.

Where: Fox (Channel 11).

When: 8 tonight.

In a nutshell: Still crazily addictive.

CAPTION(S):

2 photos

Photo:

(1) ``Vanished'' -- which begins when the crusading wife of a senator goes missing at a fundraiser held in her honor -- debuts at 9 tonight on Fox.

(2) Wentworth Miller, left, and Dominic Purcell are two brothers plotting one's escape from death row in ``Prison Break.''' The second season premiere is at 8 tonight.