In theaters

REINDEER GAMES. Directed by John Frankenheimer. Written by Ehren Kruger. Running time: 99 minutes. Rated R.

John Frankenheimer’s “Reindeer Games” opens with five recently murdered Santa Clauses lying in a bloody heap in freshly fallen snow, which, apparently, was reason enough for a man sitting in front of me to lift his arms above his head and let out a delighted whoop of post-Christmas joy.

Still, as terrific as that opening was to him, the film nevertheless comes off like a present from someone who spends far too much time at Spencer Gifts — it initially delights with its novelty, but that novelty eventually loses its shine.

The film is all crosses and double-crosses and witty one-liners at the cost of its characters, a lively group of bums who are never explored with any depth because Frankenheimer isn’t focused so much on them as he is on getting through his film’s densely packed script.

Indeed, at only 99 minutes, there is so much going on in “Reindeer Games,” so many twists and turns and endless surprises — oh, the endless surprises — that the entire production barely keeps its balance on its bumpy patch of ice.

In brief, the plot: Ben Affleck is Rudy, an ex-con who, when released from prison, starts passing himself off as his former cellmate, Nick (James Frain). He does this because of Nick’s anonymous, torrid letter-writing relationship with Ashley (Charlize Theron), a gorgeous bombshell Rudy quickly decides he wants for himself.

Through a series of convenient contrivances, that’s just what happens — Ashley’s bee-stung lips start rocking Rudy’s world — not Nick’s. But, as Nick, Rudy now finds he must accept everything that comes with being Nick, which not only includes Ashley’s enthusiastic bouts of adoration — oh, those enthusiastic bouts of adoration — but also the presence of Ashley’s sociopathic brother, Gabriel (Gary Sinise), a petty gun runner who conspires to get everyone involved in a ridiculous casino heist.

Set in Michigan, this countrified bit of film noir is certainly well oiled, proving that Frankenheimer hasn’t lost his edge; at 70, the director of “The Manchurian Candidate,” “The French Connection II” and “Ronin” skillfully keeps things moving. It’s what he’s moving that’s the problem — a film that’s layered with so many outlandish plot twists, so many far-fetched surprises, that Santa’s neat bag of tricks eventually becomes Santa’s tired old bag of jokes. Grade: C+

On video

RANDOM HEARTS. Directed by Sydney Pollack. Written by Kurt Luedtke and adapted by Darryl Ponicsan, based on the novel by Warren Adler. Running time: 131 minutes. Rated R.

With so much grim, romantic cheese clogging its heavy script, it’s no wonder “Random Hearts” collapses on screen from cardiac arrest.

In spite of having Sydney Pollack on board as its director, Harrison Ford as a Washington, D.C.-based police sergeant, Kristin Scott Thomas perfectly cast as a New Hampshire congresswoman, and a story that conspires to get these two into bed after they learn their cheating spouses died together in a plane crash, the film feels like one of those wretched transoceanic flights to Bora Bora — long and exhausting, its stale atmosphere, well, boring boring.

Not to mention morose. The somber tone Pollack strikes throughout is so depressing, it feels like the cinematic equivalent of two Valium tossed down with a vodka chaser.

Ford, as always, is built Ford tough. He’s always worth watching here, even if he does go too far with his laconic, brooding and troubled performance as a man at wit’s end. Unfortunately, the same can’t be said for Scott Thomas, who struggles throughout with an American accent that’s so uneven, it undermines a film whose script is already too random to suit. Grade: C-

Christopher Smith’s reviews appear each Monday and Thursday in the NEWS, each Tuesday and Thursday on “NEWS CENTER 5:30 Today” and “NEWS CENTER Tonight,” and each Saturday and Sunday on NEWS CENTER’s statewide “Morning Report.”