Yet although Gordon-Levitt presence helps to keep us invested in the story, you'll be left wondering how this dull, overlong film might have turned out in the hands of a less bombastic filmmaker.

But what [Snowden] mostly adds up to is a strange, disappointing movie.

Snowden's intellect is most effectively conveyed in Gordon-Levitt's eyes - watchful, sober and clouded by doubt, they are a window into his impossible ethical quandary.

The volume of the pedestal-placing and monument-building is terribly effusive.