John Halder (Viggo Mortensen) is obviously a good man. At work as a literature professor he clearly passionate about his subject, while at home he's taking care of his ill mother and running a household while his flighty wife plays the piano at all hours of the day and night.

Unfortunately for him, he's living in 1930's Germany, and being "good" isn't really high on the list of social virtues promoted by the Nazis. So when he's called into a government office for a meeting it's hardly surprising that he's worried where things might lead.

As it turns out, he needn't have: a novel he wrote a few years earlier in support of mercy killing happens to be in line with Nazi Party policy, and the Party would like him to lend his moral weight to the cause. Where's the harm in that - it's a cause he believes in after all. And if he has to join the Party as part of the deal, at least he doesn't have to join the rank and file, as there's an honorary slot in the SS just waiting for him.

You get the picture: Halder might only be taking baby steps, but each tiny step brings him closer to a conclusion that, while completely obvious long before he even puts on his SS uniform, still manages to horrify and appal.

That's in large part thanks to an excellent performance from Mortensen, who manages to both look like a stereotypical Nazi type while clearly being a sensitive, almost wimpy man who only wants to do the right thing when it's presented to him.

Jason Isaacs as his Jewish war buddy and best friend is just as good in a lesser role, managing to be both likeable and just annoying enough that when events take their predictable turn Halder's actions retain a sliver of our sympathy. Good is as powerful and gripping a depiction of a moral slippery slope as we've seen in many a year.

Rating: 3 wombats