Fox is being sued by a screenwriter who claims Kingsman: The Secret Service is based on his work, not on the eponymous comic series from a Marvel imprint.

R. Spencer Balentine claims the spy hit is based on a 2003 screenplay he wrote titled The Keepers. He says he entered the project into a screenwriting contest in 2004; it placed in the top 10, which meant his work was considered for adaptation as a comic book by Dabel Brothers Productions. Dabel and Marvel in 2006 entered into a publishing and distribution agreement, according to the complaint, which he claims gave Marvel access to his work.

Balentine claims the Kingsman screenwriters gained access to his work and used his ideas for their film.

"The Film is purported to be based on a comic book series originally entitled The Secret Service, first published in 2012 by Icon Comics (a division of Marvel) and written by Mark Millar," writes attorney Steven Lowe in the complaint. "However, several key aspects of the Film do not appear in The Secret Service comic that do appear in [Balentine's] Screenplay; for example, in the comic, there is no reference to Knights of the Round Table, no small dog companion to the protagonist, no use of holograms, and the general theme of the comic is about public service rather than an individual overcoming humble origins to achieve greatness."

The writer claims the film's protagonists, mentors and antagonists all share striking similarities to his creations, ranging from upbringing and beverage choice to disdain for humanity and vulnerability to panic attacks.

He also claims the screenplay and film have substantially similar plots, including candidacy for membership in an elite secret organization, the kidnapping of state dignitaries and hologram-assisted meetings.

Balentine is seeking damages of at least $5 million. Fox has not yet replied to a request for comment on the complaint, which is posted below.