Editor’s Note: Due to a technical problem, Reel Reviews did not run in Monday’s Style section. The NEWS regrets the delay.

In theaters

U-571. Directed by Jonathan Mostow. Written by Jonathan Mostow, Sam Montgomery and David Ayer. Running time: 115 minutes. Rated PG-13.

Lock and load, people. Arm yourselves well and take no chances. Right now in theaters, a bunch of cardboard stereotypes is lying in wait to take you down with stiff performances and preposterous dialogue.

Look sharp. Pay attention. Be wary of those plot holes. Nobody needs to be a victim here.

Unless, of course, it’s director Jonathan Mostow. He’s the director behind “U-571,” a strictly by-the-numbers submarine potboiler that has zero interest in its characters.

That’s right, troops — zero. Ironic? Hell, yes. Apparently, everyone but Mostow knows that the armed forces are supposed to be about building character. He doesn’t do so here. Not once. Unlike other submarine thrillers — “Das Boot,” “The Hunt for Red October” and “Crimson Tide,” all of which succeeded in large part because of the emotional weight given by their sharply drawn characters — Mostow isn’t at all interested in human drama.

Instead, his focus is on his plot: A German U-boat carrying the Nazi Enigma machine has been damaged in the mid-Atlantic. The United States, desperate to retrieve the machine so it can crack the Nazi radio codes, devises a mission to remove it from the crippled boat and get it into the hands of the Navy.

The particulars of that mission and its surprises won’t be revealed here, but if you’ve seen 1958’s “Run Silent, Run Deep” and 1957’s “The Enemy Below,” you’ll have a good idea of the pieces and parts that make up “U-571.”

Mostow does get a fair performance out of Matthew McConaughey as the young naval lieutenant faced with carrying out the film’s mission, but Harvey Keitel is wasted, Jon Bon Jovi is reduced to showcasing his jawline, and Bill Paxton delivers his worst performance ever. He’s so bad here, so wooden and clearly uncomfortable in his role as McConaughey’s superior officer, I kept wishing a twister would blow in and sweep him out to sea.

“U-571” isn’t a complete wash; it does generate heat in its well-staged battle sequences, and Mostow proves masterful in swinging his camera around the ship’s tight, authentically claustrophobic atmosphere. But with dialogue this bad (“This is the Navy, where a commanding officer is a mighty and terrible thing!”) and without ever knowing the people we’re asked to root for, this film, quite simply, sinks. Grade: C-

On video

Tumbleweeds. Directed by Gavin O’Connor. Written by O’Connor and Angela Shelton. Running time: 102 minutes. Rated PG-13.

Gavin O’Connor’s “Tumbleweeds” is the trailer-trash version of Wayne Wang’s “Anywhere But Here.” Of the many, many reasons audiences should run to rent it, the foremost reason is Janet McTeer’s Academy Award-nominated performance as Mary Jo Walker, a loose Southern woman with big hair and a bigger heart whose place in life is more fragile and uncertain than she’d like to admit.

McTeer, the British stage actress who recently won a Tony Award for her acclaimed portrayal of Nora in Ibsen’s “A Doll’s House,” marks her film debut here — and what a remarkable debut it is. Without a trace of her English accent, McTeer becomes Mary Jo so completely and so effortlessly, her transformation surpasses Vivien Leigh’s in “A Streetcar Named Desire.”

Certainly, Mary Jo relies on the kindness of strangers. With her 12-year-old daughter, Ava (Kimberly Brown), in tow, Mary Jo has made a life out of going from man to man — and state to state.

A natural at making wrong choices, she’s been married countless times and can never seem to get it right. She’s too quick to settle, too desperate for love and security to really care — and too insecure to do much about it. Her life is what she’s made it, and she’s made it a mess.

After a vicious breakup with a former beau, Mary Jo and Anna hit the road and head West to San Diego, where Mary Jo meets the hulking trucker Jack Ranson (played superbly by director and co-writer O’Connor), and falls into the same trap of making ridiculous compromises so she can have a man in her life.

Honest, moving and often funny, “Tumbleweeds” is a character-driven drama about relationships that never presents Mary Jo as a victim. It’s smarter than that. Instead, the film allows her to find her way with the help of a daughter who’s already seen it all at the age of 12 — and who doesn’t care to see much more.

Don’t miss it. Grade: A

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