LOS ANGELES (AP) -- The end credits of the "Batman Begins" sequel include a farewell note to Ledger, who died in January from an accidental overdose of prescription drugs; and to special-effects technician Conway Wickliffe, who was killed last September in a stunt-car accident.

"In memory of our friends Heath Ledger & Conway Wickliffe," reads the tribute included in the credits, which went up Thursday on the Warner Bros. publicity Web site.

Ledger plays the villainous Joker in "The Dark Knight," who begins a reign of terror on Gotham City that pits him against conflicted hero Batman (Christian Bale).

Arriving in theaters July 18, the movie reteams Bale with director Christopher Nolan and returning co-stars Michael Caine, Morgan Freeman and Gary Oldman. Joining the cast are Aaron Eckhart and Maggie Gyllenhaal.

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