The "Titanic 2" concept itself has been explored in various forms:
* "Titanic II" (2010) is a made-for-TV movie that features a replica of the Titanic that sets sail on its maiden voyage, encountering similar tragic events. This film is separate from the "Jack is Back" concept.
* Fan-made projects: Numerous fans have created their own "Titanic 2" stories and films, with varying degrees of production quality. The "Jack is Back" title is likely one of these fan-made ideas.
* "Titanic: The Legend Goes On" (1999) was a video game that included elements of a "Titanic 2" story, but this was also separate from the "Jack is Back" concept.
Therefore, while the "Jack is Back" title is a fictional concept, the idea of a "Titanic 2" story has been explored in various forms, mainly in unofficial fan projects.