Margot Robbie and Allison Janney score in Craig Gillespie's bizarre bio-pic -- I, TONYA

Not exactly a mockumentary and certainly not a documentary; not a comedy, though it's sometimes fall-down funny; often hugely dramatic without coming close to what you'd call a drama; I, TONYA -- director Craig Gillespie's and screenwriter Steven Rogers' oddball telling of the tale of Olympic-worthy ice-skating star, Tonya Harding, with special emphasis, of course, on her maybe take-down of competing skater Nancy Kerrigan -- is an instant genre-masher to write home about.

Mr. Gillespie, shown at right, and Mr. Rogers have contrived a style of film in which the participants often break the fourth wall and address us in the audience in order to make something clear, right a perceived wrong, or simply change their story.

From the start, and intentionally so, we're unsure of just whom to believe, though it at last comes clear that the filmmakers probably find Ms Harding -- brought to fine and invigorating life by Margot Robbie (above and below, who co-produced the film) -- the most convincing of this bizarre crew.

Most bizarre of all, and giving another of the "performances of her life" is the great Allison Janney (below), playing Tonya's inexplicably evil and crazy mother. Ms Janney is so good at whatever she does that we simply buy it -- lock, stock and barrel -- and here the actress, with the help of Mr. Rogers, just keeps surprising us with over-the-top behavior until we say, "Well, it can't get any worse." And then it does.

The film has been pilloried in some circles for the way in which it is said to treat its "white trash" characters. But since they often behave in a trashy manner and are Caucasian, this doesn't exactly seem inappropriate. And at least they are usually fun and funny, too -- except, of course, when they're beating the shit out of each other. The primary beater would be Tonya's boyfriend-and-finally-husband, Jeff, played appropriately by Sebastian Stan, below.

Also on tap for much dumb fun is Jeff's side-kick, Shawn, played to idiot perfection by the delightful Paul Walter Hauser (above, left, in the blurry background). How these guys and their cohorts go about their sleazy business provides much of the film's increasing enjoyment, even as poor Ms Kerrigan gets clobbered. (The character who is the classiest and kindest in the entire movie is Tonya's coach/mentor, played with distance, depth and feeling by Julianne Nicholson, below, left.)

While I can imagine this movie being executed in various ways that would maybe honor the story and characters in a better, more truthful, or at least quite different manner, it is supremely difficult to imagine it being anymore fun than in this genre-mashing style that Gillespie and Rogers contrive.

From that relatively new distributor, NEON and running a long but not-for-a-minute-boring two full hours, I, Tonya, opens here in South Florida tomorrow, Friday, January 5 -- in the Miami area at Regal's South Beach 18, the O Cinema Wynwood, the Tower Theater, the Cinépolis Cocnut Grove, the Landmark Merrick Park, and the AMC Aventura; in Fort Lauderdale at the Classic Gateway 4; in Boca Raton at the Living Room Theater, the Movies of Delray, and the Cinépolis Luxury Cienmas in Jupiter. The film is also playing all around the country: Click here to find the theater(s) nearest you.