'In the Fade': Cannes winner Diane Kruger is riveting

In the Fade yielded a best actress award for Diane Kruger at the Cannes Film Festival, and watching this wrenching movie, it's easy to see why.

Kruger plays German woman, Katja, who loses her husband (Numan Acar) and son to a terrorist bomb, and she's excruciatingly good at showing a woman in the throes of intense grief and anger.

Adding to Kruger's command of the picture is the way the story isolates Katja — her grief leaves her increasingly estranged from her relatives, from the investigation, from the world that keeps turning around her as she remains frozen by loss.

The aftermath exposes tensions within her family, with her husband's relatives. The police are oafishly fixated on the dead man's previous conviction for a drug offense, convinced the crime is drug-related.

Katja knows (and we know) they are wasting their time. She saw the bomber as the perpetrator left her husband's office — blonde, young, female, and "as German as me," a line that comes to have complex meaning as the story unfolds.

Katja's husband was a Turkish immigrant, and she suspects the bombers were neo-Nazis targeting foreign-born citizens (the director, Fatih Akin, is also of Turkish descent, and based the story on recent neo-Nazi crimes committed against immigrants).

What Kruger does is remarkable — showing Katja paralyzed with grief, but doing so in a way that does not paralyze the story. The camera stares remorselessly as she cries in her son's bed, or as she watches video of a family vacation — the narrative barely moves, but Kruger keeps us riveted with every emotional turn.

By the time the police get their act together and the case goes to court, Katja has evolved into a bristling icon of righteous fury (an icier version of Mildred in Three Billboards Outside Ebbing, Missouri) — such a towering psychological presence in the courtroom that the unnerved defense attorney wants her barred from the proceeding.

But, as she is also a witness, she has the right to stay. The mechanics of the German justice system (a panel of judges, different rules of conduct for attorneys, standards for testimony) will seem a bit odd to U.S. audiences, but the dynamics of the trial are engrossing, sometimes surprising.

There is a strangely moving moment between Katja from the father of one of the accused, a decent man who's own soul has been scraped empty by the knowledge that his child had grown to become, as he puts it, "wicked, cowardly and stupid."

Katja's rage (she dresses in black, but more like a punk ninja than a widow) is such that she's not likely to get everything she wants from the legal system — she describes much of what goes on in court as "chitchat" (the movie mixes English with subtitled German). Later stages of the movie are devoted to Katja's consideration of extralegal "justice."

The concluding section of In the Fade feels weaker, but it gives Kruger new space in which to work. Katja, so fierce and finely drawn, becomes of figure of ambiguity — a woman who may surrender to hate, or perhaps a woman who sees hatred at work in the world, and wonders if she wants to be a part of that world  any longer.