Rịba ama amaokwu a dị n'okpuru ma zaa ajụjụ ahụ mgbe e mesịrị n'otu asụsụ ahụ dị ka amaokwu ahụ:  Passage: Nolan si n'ihe nkiri Joker nke mbụ e bipụtara n'afọ 1940, na akwụkwọ akụkọ nke afọ 1988 bụ The Killing Joke, na usoro nke afọ 1996 bụ The Long Halloween, nke na-akọghachi mmalite nke Two-Face. A na-akpọ Batman "Dark Knight" na Batman #1 (1940), na akụkọ Bill Finger dere. A na-ese The Dark Knight na Chicago, yana n'ọtụtụ ebe ndị ọzọ na United States, United Kingdom, na Hong Kong. Nolan jiri igwefoto ihe nkiri IMAX 70 mm mee ihe nkiri ụfọdụ, gụnyere ọbịbịa mbụ nke Joker na fim ahụ. Warner Bros. bidoro mepụta mkpọsa ahịa ahịa maka The Dark Knight, na-emepe weebụsaịtị nkwado na trailers na-egosipụta nseta ihuenyo nke Ledger dị ka Joker. Ledger nwụrụ na Jenụwarị 22, 2008, ọnwa ole na ole mgbe emechara ihe nkiri ahụ na ọnwa isii tupu a tọhapụ ihe nkiri ahụ site na ngwakọta na-egbu egbu nke ọgwụ ọgwụ, na-eduga na nlebara anya siri ike site n'aka ndị nta akụkọ na ndị na-ekiri ihe nkiri.  Ajụjụ: N'ime eluigwe na ala batman, afọ ole ka e bu ụzọ webata Joker?
Afọ 1940