Heath Ledger died of an overdose in his Manhattan apartment two days ago. The virulent spread of the news was fuelled by the shock of his death, as well as the affection for the 28 year old actor many fans developed from his breakthrough performances in films like 10 Things I Hate About You and A Knight’s Tale. While he also starred in some rather less loved films – The Patriot comes to mind as a marked dip in his short career – he was, at the time of his death, enjoying a period of intense popular and critical acclaim. His astonishingly moving performance in 2005′s Brokeback Mountain gained him an Oscar nomination, and introduced him to his ex-partner Michelle Williams who survives him with their two-year-old daughter Matilda. His second performance with Williams in last year’s I’m Not There, the structurally and stylistically daring biopic of Bob Dylan in which he played one of many disparate Dylan incarnations, garnered him similar critical praise.

However, it is in the run up to this summer’s The Dark Knight that Ledger’s death will be most deeply felt. Expectation of his performance as the Joker in the sequel to Christopher Nolan’s Batman Begins began after prolonged uncertainty at who would take the role, and heightened at the release of the first shots of Ledger which showed his face, once a pretty-boy hallmark, mauled by the Joker’s decaying, deathly-white greasepaint and split in two by a bloody scar of a grin. This anticipation reached hysteria at the release of a full length trailer this December, which gave a real look at Ledger’s transformative performance, his voice unrecognisable as it lurches between shrieking, manic laughter and the wonderfully terrifying growling of the question ‘Why so serious?’

This question is currently the hook of the film’s arresting advertising campaign, though presumably not for much longer; one wonders how long Warner Bros can continue to use the image of the deceased actor scrawling those words and his grin in blood, even if suicide is no longer considered to be the cause of his death.

Indeed, the connection between the mindset of his unhinged, psychopathic Joker and Ledger’s own may prove uncomfortable viewing when the film is released this July. His approach to creating the character and his voice has been widely reported, Ledger locking himself in a hotel room and recording an in-character diary while barely sleeping. A November 2007 interview for The New York Times which recalls this period is now eerie reading, the interviewer admiring his attention to detail with descriptions of the actor’s frenetic behaviour during the interview, lack of sleep and harsh self-criticism. That in this interview his performance in I’m Not There is likened to James Dean is worryingly prescient.

While the fruits of that labour will at least be revealed on The Dark Knight‘s release, uncertainty now surrounds the films Ledger was working on at his death, such as Terry Gilliam’s typically mad-sounding The Imaginarium of Doctor Parnassus. It seems Gilliam continues to carry the curse of production problems borne of Brazil, most dramatically shown in the disaster ridden The Man Who Killed Don Quixote (which exists now solely in Lost In La Mancha, a documentary about the problems the production faced) and in his repeated attempts to make his film of Alan Moore’s Watchmen.

Ledger’s shocking death will inevitably shape our appreciation of the actor’s oeuvre in years to come, and it is particularly likely that his performance in The Dark Knight will always be viewed through that lens. It is always tempting to for audiences to cast stars in the mould of our James Deans and River Phoenixes, and in Heath Ledger another great talent has been lost.