- Creator-Preferred Adaptation: Judd Winick, who wrote the original comic version and the film, has admitted to prefer the film. The primary reasons are to due to Adaptation Distillation and patching up some of the odds and ends.
- The Danza: Bruce Greenwood voices Batman, aka Bruce Wayne.
- Fake American: Canadian-born Bruce Greenwood as Batman, an American.
- Playing Against Type: John DiMaggio as The Joker.
- Real-Life Relative: Teenage!Jason is voiced by Vincent Martella while Young!Jason is voiced by his younger brother, Alexander Martella.
- Role Reprise: In the French dub, several voice actors from previous adaptations reprised their roles here:
- From Batman (1989) and its sequels: Jacques Ciron as Alfred.
- From The Batman: In addition to Alfred, Adrien Antoine as Batman/Bruce Wayne and Alexis Tomassian as Nightwing/Dick Grayson.
- From Batman: The Brave and the Bold: In addition to Batman and Nightwing, Xavier Fagnon as the Joker and Jean-Claude Donda as Ras Al Ghul.
- Self-Adaptation: As noted above, Judd Winick, the author of the original comic, also wrote the film.
- What Could Have Been:
- The film was originally going to be R-rated, but Warner Animation convinced the staff to tone it down to PG-13. The preview of the movie included with Justice League: Crisis on Two Earths contains clips of the R-rated version of Joker killing Jason, which are noticeably bloodier and more violent than the final product.
- The prologue based on A Death in the Family was not originally going to be featured at all. However, Bruce Timm suggested Judd Winick to feature it for audiences unfamiliar to the character of Jason Todd.
Trivia / Batman: Under the Red Hood