It's a searing indictment—one that we watch his mother and father silently absorb from their seats across the courtroom.
We then flash back to their home life, if you can call it that—crammed into a crumbling slum apartment where opiates are dissolved just inches from the mattress on which half a dozen kids lie sleeping.
Zain does what he can to protect his siblings—he's tough and streetwise despite his size—but when he can't keep his folks from sending off his eleven-year-old sister to be married to the landlord, he leaves.
He lives on the street, and looks for work in a garish, seaside amusement park, where he meets a pink-and-blue-costumed Cockroach-Man who claims to be Spider-Man's cousin, and an Ethiopian cleaning lady (Yordanos Shiferaw) with a baby (Boluwatife Treasure Bankole), but no immigration papers. If he'll keep the baby safe, she decides, she'll give Zain shelter, a home away from home.
Had Charles Dickens lived in modern-day Beirut, he might have penned a story like Capernaum—feisty, resourceful kid stealing food for his adopted family, caring for an infant as life takes cataclysmic turns involving human traffickers, scam artists, cops.
Nadine Labaki has written and directed a couple of lovely small films, but nothing suggesting she could make an epic like this. Or shepherd a first-timer like her young star to such an accomplished performance.
That he shares his name, Zain, with the character he portrays is very much the point. All of her actors are non-professionals, cast because their lives resemble those of the folks in the story she's crafted. They don't just play these parts, they've lived them.
On screen, they're surrounded by images both tender and wrenching: a mother in jail squeezing her breast-milk onto the floor, sobbing to her absent infant that she's sorry; a bedtime that's a tangle of children's arms and legs; bird's-eye shots of a shantytown stretching for miles.