Say the words "political dissident," and you tend to think of a deadly earnest character. But the first glimpse you get of Chinese activist-artist Ai Weiwei in Alison Klayman's sharp-eyed documentary, "Ai Weiwei: Never Sorry," instantly conveys the man's antic wit.

The question he's pondering as the film starts: Can cats open doors?

It turns out that one of the 40 cats wandering the grounds of Weiwei's studio can do just that — and the filmmakers, hilariously, catch the kitty in action. For Ai Weiwei, though, the cat's trick is serious business. After all, if a cat can open a door, what might not a determined dissident achieve?

Quite a lot — but, as the film demonstrates, not everything. And the personal cost, when you pit yourself against an authoritarian regime, is formidable.

Born in 1957, Ai Weiwei was the son of a poet who also ran afoul of the Chinese authorities and was exiled to western China for "re-education" for 19 years. His father's experience seems only to have egged the artist on in his anti-regime stance.

The film gives vivid examples of Ai Weiwei's highly conceptual yet visually striking art. The most powerful is a mural commemorating the 70,000 lives lost in a 2008 Sichuan earthquake. In it, Ai Weiwei uses 9,000 children's backpacks to spell out, in Chinese characters, "She had been happy living in this world for 7 years" — a quotation from the mother of one of the victims. (Children were disproportionately among the victims, due to shoddy school construction.)

Klayman notes that Ai Weiwei's 12 years in New York (1981-1993) shaped his passion for free expression. And art, she makes clear, isn't his only outlet. His use of Twitter is downright poetic. (Sample tweet: "There are no outdoor sports as graceful as throwing stones at a dictatorship.")

By film's end, however, after being beaten, jailed and intimidated by the authorities, he's more a wary eyewitness to repression than a prankster-provocateur. And that makes "Ai Weiwei: Never Sorry" a sobering, cautionary tale.

Michael Upchurch: mupchurch@seattletimes.com