The Other Side/Al otro lado (Sun., July 30, 9 p.m., $5, Liberty Lands Park, Third and Poplar sts. / Tue., Aug. 1, 11 p.m., WHYY-TV) These two recent documentaries share more than a title. Both Bill Brown's The Other Side and Natalia Almada's Al otro lado explore the border between the U.S. and Mexico, and muse on the extent to which the permeable, contested boundary both divides and creates culture. The most poignant images in both are of makeshift way stations set up in the desert north of the border, hidden oases for illegal immigrants that reveal how dangerous, and yet how established, this form of relocation is.

Brown, who arrives in Philadelphia periodically with new work in tow, is a bemused essayist of submerged cultural conflicts; in 1999's Confederation Park, he observes how the violent history of Quebecois separatism lives on in passive-aggressive attacks on bilingual hand-dryer instructions. The Other Side returns Brown to his native Texas, but he still comes across as an outsider, training his 16mm camera on deserted still-lifes while he recalls enduring periodic ID checks on I-10, hundreds of miles from the nearest border. As in Confederation Park, where Brown playfully hopped across borders on a scaled-down sidewalk map, he treats boundaries with breezy disdain, calling the line between the U.S. and Mexico "a make-work project for land surveyors and border cops." Not surprisingly, Brown is especially keen on the sister cities of El Paso and Ciudad Juarez, where he spots cars with bumper stickers supporting candidates in the U.S. and in Mexico. A small park to which both countries have laid claim in the past is, he says, "a place where the idea of nationality is up for grabs."

Al otro lado

The Other Side doubles as an attack on the jingoist upsurge of recent months, quoting an unseen observer who says that U.S. efforts to stem illegal crossings have only redirected them to "the most inhospitable and deadliest parts of the desert." But Brown doesn't have Chris Marker's knack for didactic poetry; the shifts from detached observation to low-key activism can be jarring, especially when your ears are processing cultural criticism while your eyes are looking at a giant yellowjacket statue. Brown will present the film at Small Change's Liberty Lands "bike-in."

Where The Other Side looks resolutely southward, Natalia Almada's Al otro lado constantly crisscrosses the border, shifting mainly between Los Angeles and Sinaloa, Mexico. Almada, who was born in Sinaloa, focuses on the composers and performers of corrido, a traditional ballad form whose mellifluous melodies contrast with unvarnished portraits of daily life. The songs have a jarring immediacy, especially when Almada films them being made up on the spot. As one composer puts it, "I could have been a journalist, but I can't write."

In Sinaloa, many corridos are concerned with drug smuggling and have taken on the flavor of gangsta rap, a kinship cemented by the 1992 murder of corrido star Chalino Sanchez, whom one Angeleno calls the genre's Tupac. Magdiel, an aspiring Sinaloan singer, says his songs are most popular in prison. With lyrics like, "In my nose, some cocaine, in my pocket, my cell," it's not hard to see why.

Al otro lado intercuts Magdiel's preparations for an illegal border crossing (paid for with a custom-made corrido boasting of his coyote's prowess) with the experiences of singers who've already made it. The group Los Tigres del Norte, christened by a U.S. customs agent, sing of a desire to return home (fulfilled at a triumphant concert) and proclaim, "I didn't cross the border, the border crossed me." Trimmed by 15 minutes from its theatrical version, Al otro lado skimps a bit on corrido's backstory, but it's a graphic illustration of music's power to cross borders and capture history.

On Dangerous Ground ($49.98 DVD) Even among Nicholas Ray movies, On Dangerous Ground is overlooked, without the punched-up dialogue of They Live by Night or the operatic scale of Johnny Guitar. But it's among the most nakedly emotional of Ray's great works, at once taut and poetic, like the man himself.

Available as part of the third volume of Warner Bros.' Film Noir Classic Collection (along with Anthony Mann's Border Incident and three others), On Dangerous Ground was released in 1952, at the end of Ray's astonishingly prolific run at RKO (six movies since 1949, plus two more for Columbia). Beginning as the story of a hard-boiled city cop (Robert Ryan) who gets a bit too aggressive in questioning his prisoners, the movie waits half an hour before shipping him upstate, where the disgraced Ryan is literally sent to cool off. Assigned to investigate a young girl's murder in a snowy small town, Ryan spends as much time preventing the girl's bloodthirsty father (Ward Bond) from gunning down the fleeing suspect as he does trying to solve the crime. Wandering through the snowy terrain, a moral wasteland as bare as the African desert in Ray's Bitter Victory (or the Coen brothers' Minnesota), Ryan and Bond stumble on a cabin inhabited by the blind Ida Lupino, who instantly senses a kinship with Ryan that he is slow to recognize. Lupino's performance is almost hilariously affected ("Tell me ... how is it ... to be a cop?"), but it only enhances the strangeness of Ryan's frigid exile, the sense that he's stumbled into territory where he might get lost for good. An Ivy League boxing champion, Ryan rarely got the chance to be both tough and tender on the big screen, but Ray understood the way a wounded soul might lie beneath a tough, even frightening, exterior. (He pulled the same trick with Bogart in In a Lonely Place and Mitchum in The Lusty Men). Warner Bros.' disc does the best with a damaged source, and Dana Polan's commentary fills in a wealth of production history detailing the movie's frequent reshoots and restructurings.

(sam@citypaper.net)