Having found massive success with Game of Thrones, the HBO fantasy epic that premieres its fifth season on April 12, George R.R. Martin is looking to expand his TV fortunes.

The Game of Thrones author, who has an overall deal with HBO, is on board as a producer for a science fiction period drama with the pay cabler, which was first reported by Entertainment Weekly.

The series would be called Captain Cosmos and centers on a young science fiction writer in 1949, at the dawn of the TV age. Z Nation coexecutive producer Michael Cassutt is writing the series, which is in the early stages of development.

Aside from Game of Thrones and Captain Cosmos, Martin is currently finishing writing The Winds of Winter, the long awaited sixth installment of his Song of Ice and Fire series, from which the HBO epic is based on.