In Sangre de Mi Sangre, bad boy Juan (Armando Hernández), escaping from some thugs in a Mexican border burg, inadvertently finds himself in a van filled with illegal immigrants on their way to New York. He encounters Pedro (Jorge Adrián Espíndola), who plans to meet his father for the first time, bearing a letter written by his dead mother. Juan heartlessly fools the boy into trusting him and makes off with his every possession, assuming Pedro’s identity upon arrival in the city. He finds Pedro’s father, Diego (Jesús Ochoa), who is far from the rich restaurateur described in his letters, but a lowly, perpetual grouch of a dishwasher. Meanwhile, poor Pedro is adrift on New York streets but befriends a feisty, drug-addicted prostitute, Magda (Paola Mendoza), who offers to help him find his papi, but only for a price.

Few modern movies have the visceral excitement and heartbreaking, lived-in reality of this one, which, in its compelling immediacy, recalls the great works of Italian Neo-Realist cinema. When the miserable, non-English-speaking Pedro suddenly finds himself completely alone and penniless in a pitiless Big Apple, you excruciatingly feel his anguish as fully as anything in a De Sica film or an early Griffith drama with a Gish heroine. With searing empathy, writer-director Christopher Zalla makes you realize that bad luck can befall anyone, especially these days, rife as they are with identity theft of every imaginable sort. Although not Mexican himself, Zalla has fully absorbed immigrant culture, and the gritty authenticity of his work is unquestionable. He obviously knows from poverty, too, but is able to discern the odd moment of beauty in the gutters and squats of the outer boroughs. He keeps the pace feverishly fast and his film is bewilderingly crowded with incident, like life in present-day New York itself, where everyone from the richest to the most disenfranchised is scrambling to make it.

Zalla’s high taste level evinces itself especially in his sparing use of music: Where a lesser director would go right for the sentimental jugular with sappy themes or predictable hard-driving rap, Zalla uses only an occasional percussive beat on his soundtrack, which adds just the right stylization and urgency to the action. He does slow things down in a dreamy dance-hall sequence where a Mexican singer croons a mellow old-fashioned love ballad, as immigrant men pay and sway with their buxom hired partners.

The film is brilliantly cast in a way to make you care vitally about every character. Juan is a thoroughly reprehensible scamp, but the lusciously handsome Hernández floods the character with a volatile charisma reminiscent of Robert De Niro in Mean Streets, with a little Tony Curtis in Sweet Smell of Success thrown in for good measure. He’s the nastiest born hustler, yet utterly irresistible. For his part, the appealing Espíndola has many a teary scene, but such is the actor’s conviction and naked vulnerability that these never descend into the bathos they so easily could have. After this film, both actors should be as hot as Y Tu Mamá También’s Diego Luna and Gael Garcia Bernal. (Indeed, Hernandez has already been teamed with these actors in Carlos Cuaron’s upcoming Rudo y Cursi.)

That grand Mexican veteran actor, Jesús Ochoa, instills the humorless drone Diego with a lifetime of bitterness, miserliness and loneliness, sitting alone in his squalid apartment, stitching silk roses for an extra dollar a pop. (There’s a faint, intriguing yet unforced whiff of homosexual attraction as well, when the ingratiating Juan begins to get under his tough old hide.) Mendoza takes a sketchily drawn character and makes her a fascinating, complex born survivor of every hard knock, who’s believably seen and done every wretched thing imaginable.