Acclaimed Flop: While not as universally beloved as Don Bluth's previous efforts, it still found its fans and admirers among critics despite being pummeled at the box office by the release of The Little Mermaid. It quickly went on to be a huge hit on VHS.
When the heavenly whippet looks in Charlie's records, his mother and father are named "Loni" and "Burt", and look like canine versions of Loni Anderson and Burt Reynolds (who were together at the time.) Loni also appears in the film as one of Charlie's "close friends".
Don Bluth's birthday is also September 13, 1937. The idea that every human year is seven dog years is a myth — Charlie is about 25. Even though he seems older.
Celebrity Voice Actor: As well as Burt Reynolds voicing Charlie, the German dub has him voiced by the equally rascally Harald Juhnke.
Executive Meddling: We were originally going to get to see Charlie's body flying off the pier (a rare example of a meddling executive making a good call). Interestingly, many book adaptations of Don Bluth films include unused artwork; ergo, the tie-in book for this film showed a very clear silhouette of Charlie's body flying alongside the car...
Burt Reynolds is on record for saying that there was supposed to be some casual swearing in the dialogue, all of which was removed to make the film more appropriate for children. An artifact of this can be heard on the soundtrack album, when Charlie angrily mumbles to himself "Damn, that Carface, I'll kill him!" In the movie, the "damn" is awkwardly cut out.
Keep Circulating the Tapes: Not the movie, but the original Beth Brown book the film was inspired by has been out of print for decades and is very hard and expensive to find.
Name's the Same: Invoked. The title came from a book Don Bluth's teacher had read to him when he was a child. It was an anthology of stories about a noir-style dog detective. Bluth only remembered the title and looked it up years later when he became a filmmaker, but after writing one treatment of a straight adaptation under the name "Canine Mysteries" decided that he didn't like the story and created an entirely new one off of the title.
Otherwise averted in the entire series, where many of the characters are played by professional singers.
Subverted, considering the fact that Burt Reynolds, Dom DeLuise, Ernest Borgnine, and Charles Nelson Reilly all get songs over the course of the series. It seems that the one thing each installment had in common was giving songs to actors who couldn't sing.
The Other Darrin: Save for Dom DeLuise and Charles Nelson Reily as Itchy and Killer, respectively, none of the actors from the first film are in the sequel or TV show.
Troubled Production: The sequel, according to the directors, was originally animated in Dublin, Ireland (where Bluth's original studio, which produced the first film, used to take place before that). But then, after Screen Animation Ireland, the Dublin studio in charge of the animation, shut its doors, the animation has to be outsourced to several studios in countries like Taiwan, Korea, Canada, and Denmark in order for the film to meet up the deadline.
Wag the Director: Burt Reynolds and Dom DeLuise, who had developed a repertoire with one another after starring in several movies together, insisted that Don Bluth leave the room during recording sessions so that they could improvise off one another better. Despite his initial chagrin, Bluth would later admit that some of the film's best lines came from their improv.
Bluth originally conceived the film as a short entitled "Canine Mysteries" as part of a package film, which would have also included an adaptation of The Velveteen Rabbit. Based on some recently-shared concept art, the dogs would have had more direct interaction with humans.
Several seconds of the Hell sequence were cut for being too frightening. The full version has recently surfaced.
Burt Reynolds originally read his part with a more cartoonish "doggie" (read: Scooby-Doo) voice, which nobody liked. Reynolds persisted, saying it was cute, until Dom DeLuise pulled him aside and said "Burt, don't be an asshole," at which point he dropped it.
Write Who You Know: Charlie was designed after Gary Goldman's dog Burt (named for Reynolds). Goldman first found the pooch chasing after Reynold's car leaving their first lunch meeting.