Dawson is best known for her roles in "Rent," "Alexander," "Sin City" and "Death Proof."
"True Believer" is based on an original concept from Dawson, David Atchinson -- Dawson's co-author on the Image Comics book "Occult Crimes Task Force" -- Matthew Spradlin and Tom Feister.
The network describes it as "a quirky, contemporary dramedy about a 20-something comic book nerd who hires a washed-up real-life superhero to be his crime-fighting sidekick and teach him the ropes. Together, this unlikely duo set out to save the world."
Dawson will serve as executive producer with Atchinson and Spradlin on board to write, SCI FI Channel said.
Feister will consult on the project.