In 1997, he appeared out of the blue to grab the best actor Oscar for Shine. His grand entrance was followed by a productive but relatively unnoticed few years.
Aside from roles in Elizabeth and Shakespeare in Love, Rush made little impression for a couple of years.
Now, however, he is again defying attempts to underestimate him with an Oscar nomination for best actor for his role in Quills as the Marquis de Sade.
Rush - a willowy, quirky-looking actor with wild hair and a glint in his eye - seems made for the role as the outrageous 18th Century French writer.
By the same token, it is easy to see why Rush won the part of tormented genius David Helfgott in Shine - and why Australia has long considered him one of its best kept secrets.
Rush was born in Queensland, in a little town called Toowoomba where he was born in 1951.
He did an arts degree from the University of Queensland before entering the theatre.
Pantomime
Time at Brisbane's Queensland Theatre Company was followed by a two-year stint in Paris.
Here, Rush showed early signs of individuality by studying pantomime at the Jacques Lecoq School of Mime.
Rush went back to Australia in the late 70s to resume his stage work. Without much money, he shared a flat with an equally impoverished young actor - Mel Gibson.
The two were co-stars in a local production of absurdist play Waiting for Godot - Rush was gradually honing his taste and talent for the unusual and outrageous.
The early 80s found Rush with director Jim Sharman's Lighthouse Theatre troupe.
But he also began dabbling in the movies with his first film role in 1981 in romantic comedy Hoodwink.
It was followed by minor parts in small-time movies such as comedy Starstruck and drama Twelfth Night. But in 1996, Rush got his big international break in Shine.
Indulgent
The film's producers originally had trouble securing capital for the film as the financiers wanted a big name - which, at that time, Rush was not.
However, the actor proved them wrong with his passionate performance as the unbalanced, tragic pianist Helfgott.
He won a best actor Golden Globe, followed by the Oscar for best actor.
His success went on to earn him less glorious - but nonetheless respectable - roles.
These included parts in Gillian Armstrong's Oscar and Lucinda in 1997 and in Billie August's screen version of Les Misèrables.
But it was the costume dramas, Elizabeth and Shakespeare in Love, that allowed Rush to indulge his skill for eccentric characterisation.
Elizabeth saw him play the queen's sinister confidant while Shakespeare in Love had him take on the part of the wacky, debt ridden theatre owner. This second role again saw him nominated for a best supporting actor Oscar.
In 1999, Rush jumped from one madcap role to the next.
Art form
In Mystery Men he played the dastardly Casanova Frankenstein with an unlikely mix of co-stars, including Greg Kinnear and Ben Stiller.
The same year, he played an eccentric millionaire who invites a few guests - including Elizabeth Hurley - over for tea and terror in the remake of William Castle's 1958 classic, The House on Haunted Hill.
Luckily, writer and director Doug Wright came along just at the right time with Quills - an outrageous take on the last 10 years of the censored, sexually-explicit Sade's life.
Rush was chosen to head-up a star-packed cast including Kate Winslet, Sir Michael Caine and Joaquin Phoenix.
The result has been explosive, with Rush praised for his unadulterated showmanship.
Rush continues onwards and upwards. Next he will be seen in thriller The Tailor of Panama with Pierce Brosnan.
And the chances are that he will be back again and again in a wide variety of challenging character roles.