[7] These characters include Wesley Gibson, Kick-Ass, Hit-Girl, Eggsy Unwin, Nemesis, Duke McQueen, Edison Crane, and others, while the events of The Unfunnies, Jupiter's Legacy, and Supercrooks exist as popular fiction within the world of the Millarworld.

The imprint was launched in 2003 with the publication of the miniseries Wanted, followed by Kick-Ass – The Dave Lizewski Years, Kingsman, War Heroes, and The Magic Order, and later the crossover series Big Game.

Wanted, published by Top Cow Productions, was loosely adapted into a feature film of the same name by Universal Pictures, released on 27 June 2008.

[2] Chosen, published by Dark Horse Comics, was described by Millar as a sequel to the Bible, and has been optioned by Sony Pictures.

[18][19][20][21][22] In May 2023, it was revealed that Big Game is actually a sequel to Wanted, Millar's first creator-owned work, and follows Wesley Gibson and the Fraternity teaming up with Matthew Anderson / Nemesis to take down the latest wave of superheroes that have popped back up in the world following the actions of Dave Lizewski / Kick-Ass.

[23] In December 2023, it was revealed that Millar had signed a deal with Dark Horse Comics to become the new publisher of the Millarworld titles.