Heroes of the Zeroes is Nick Rogers’ daily, alphabetical look back at the 365 best films of 2000 to 2009.

“Existentially troubled hitman” was a Zeroes-cinema plot du jour most thoughtfully evoked by The Matador and 2000’s Panic, which barely eked out a release once test audiences turned on this hot Sundance Film Festival acquisition.

Maybe that’s because Henry Bromell’s film doesn’t rest for the easy, ironic gimmick of a man whose trade demands silence seeking sounding boards.

Arguing William H. Macy is the last actor fit to be a hitman discredits how he makes Alex the perfect hitman —an unassuming schlub who bumps into a man, fatally bumps him off and makes a modest gesture of apology as he continues walking. He’s been trained in a family business cultivated by his father, Michael (Donald Sutherland).

To a shrink (John Ritter), Alex discusses his creeping tedium, indifferent marriage (to Tracey Ullman) and doted-upon son Sammy (David Dorfman). Soon after, he contemplates an affair with a fellow patient (Neve Campbell) and realizes Michael has family-business designs on sensitive Sammy.

Sutherland’s ghoulishly underhanded granddad is his best role since Backdraft. Dorfman gives the Zeroes’ most effortless child-actor performance.  And Bromell gives substantive traits to Ullman and Campbell in what could’ve been stick-figure roles.

But Panic is Macy’s show — as Alex realizes that his deep-seated unhappiness has been almost as invisibly destructive as him and that there’s a difference between feeling angry and acting upon it.Singlehandedly, Macy turns Panic into a slimmed-down American Beauty — a passive man lashing out to break a cycle of dissatisfaction and familial strife for happiness, however fleeting.