Heath Ledger's family attended the New York premiere of The Dark Knight in New York on Monday night.
Kim Ledger - the father of Heath, who died in January from an accidental prescription drugs overdose aged 28 - and his wife, Heath's stepmother, Ines, avoided the red carpetbut made their way into the cinema through a back entrance to watch Heath's performance as The Joker in the new Batman movie.
As he left the cinema, Kim gave photographers the thumbs up sign, and told reporters the film was "very good".
Heath's co-stars were also at the exclusive event, where they paid tribute to the actor.
Christian Bale, who plays The Caped Crusader for the second time, said: "Working with Heath was fantastic. He steals the movie and I'm quite happy to say that. He's a hell of a talent and created a Joker that's very iconic and one that will become a classic portrayal of the ages."
Sir Michael Caine, who plays Bruce Wayne's butler Alfred Pennyworth in The Dark Knight, added: "I couldn't believe the intensity and ferocity of the performance. But when we were sitting down between takes, he was completely ordinary. He wasn't preparing himself or saying 'Please leave me alone, I've got to do this'. Instead he was talking to me.
"We would sit and chat and have a cup of coffee, then suddenly they'd say, 'We're ready, Heath', and he'd go straight into The Joker.
"His energy was astonishing, especially when it came from this kind of calm. He's certainly the best villain I've ever seen."
Heath's performance as The Joker - a part made famous by Jack Nicholson in 1989 movie Batman - is already receiving rave reviews, and critics are tipping him for a posthumous Oscar nomination at this year's ceremony.
