The rights to the book series have been optioned for film adaptation several times, but no production has moved forward. As of right now, there's no confirmed movie in development.
However, if a Skulduggery Pleasant movie were to be made, some potential titles could be:
* Skulduggery Pleasant (straightforward and to the point)
* The Skeleton Man (referencing Skulduggery's identity)
* The Last Apprentice (referencing the main character)
* Dark Days (referencing the series' dark fantasy elements)
* The Necromancer's Apprentice (a more specific title emphasizing the magical elements)
Ultimately, the title will depend on the direction the filmmakers take with the adaptation and the overall tone they want to convey.