The X-Men Legacy writer is working with Leonard Kirk (Captain Britain and MI13) on the title, which is returning as part of Marvel Comics' revival of the CrossGen line.
The original Sigil was a space opera featuring Samandahl 'Sam' Rey, a former-soldier who is branded with a mysterious mark that endows him with fantastic abilities.
"For our series we've got a female protagonist, but we've kind of kept the name," Carey told CBR. "She's Samantha Rey and her initial situation is very different than the protagonist of the previous series.
"Like Samandahl Rey in the original series, by virtue of her possession of the Sigil she's enlisted, whether she likes it or not, in a huge conflict. It's a conflict that goes far beyond anything she's ever experienced in her life.
"This opening arc doesn't stray into space opera territory, although because it is such an open concept and because of the nature of this war that our Sam has to fight in, it can almost become anything. It can take her anywhere; to any time, place or context. We've got a huge number of reveals stacked up, which will exploit some of that freedom."
Sigil will debut in March alongside another relaunched CrossGen title - Ruse.