I, Tonya

(MA15+) ★★★½

Director: Craig Gillespie.

Cast: Margot Robbie, Sebastian Stan, Allison Janney, Julianne Nicholson, Caitlin Carver, Paul Walter Hauser, Bobby Cannavale.

"The baseball bat we broke her knee with was this big."

Of course this true story was always going to become a movie. And not just a daytime movie special, but a proper movie.

It's a story that has everything - intrigue, crime, sport, passion, and a lead character trying to live out the American dream of rising above her station and representing her country.

But best of all it has very stupid people doing incredibly stupid things all because of a fairly stupid sport (there, I said it - take that ice-skating).

For those who don't remember those fateful weeks back in 1994 when the world obsessed over "the incident" (as it's referred to in the film), this is the story of Tonya Harding, who was the greatest ice skater in the world for a short period of time. The majority of the film serves as a biopic for Harding, providing much-needed context for the moment on January 6, 1994, when Harding's main rival Nancy Kerrigan was kneecapped by a lone male following a skate comp.

What ensued was a tabloid feeding frenzy, the likes of which the freshly born 24-hour media cycle had never seen before.

Central to I, Tonya is Robbie's masterful performance as Harding. A desperately unlikeable character, Harding is made somewhat palatable by Robbie's honesty in the role, and a script that does its best to find reasons to barrack for her. Robbie is the hero of the piece - she hits Harding's many moods with ease, rolling through vulnerable, strong, hilarious, stupid, determined, vicious and desperate. It's the best performance of Robbie's short career-to-date.

Not to be outdone is Janney as Harding's despicable mother. It's a role Janney easily navigates into that difficult stream between comic relief and hissable villain. Ditto for the under-rated Stan, who makes the character of Jeff Gillooly feel like a real person and not a one-dimensional bastard. And Hauser is definitely in the votes for his laugh-out-loud turn as Shawn Eckhardt, Harding's supposed bodyguard.

The film's delivery as a quasi-mockumentary skates or stumbles on the strength of its cast, so thankfully its a strong line-up of players. Otherwise I, Tonya would not be half the movie it is. This faux-doco approach is somewhat haphazard - on top of having to-camera interviews with the characters, it also occasionally breaks the fourth wall mid-drama to add a thought bubble it could have probably added in a to-camera bit. These meta-moments are too few to get used to and as a result they pull you out of the action. It's certainly not a deal-breaker - in fact, more of them might have made everything fit together more consistently.

For all its talk of subjective truth, the film could have done with some more varied viewpoints to back up that point. It could have also used some more of Kerrigan - the film is called I, Tonya for a reason, but a bit more context around Harding's frenemy would have been helpful.

Another issue is the too-obvious CG-splicing of Robbie's face on to the real-life skaters pulling off the incredible skate performances in the film. Maybe some of you won't notice it, but to experienced eyes it's distracting.

Despite these criticisms, I, Tonya is a joy to watch. It's a funny retelling of a head-scratchingly idiotic tale, with some wonderfully stupid characters telling it. The production design, costuming and make-up is also great.

But this is really all about the performances, in particular Robbie's. If nothing else, it's worth watching for that alone.