Once Upon a Time alum Colin O'Donoghue is replacing Joe Dempsie in National Geographic's upcoming astronaut drama, The Right Stuff.

Deadline.com reported British-born Dempsie had to bow out of the role of Gordon Cooper due to visa issues.

Cooper piloted the last and longest Mercury spaceflight in 1963.

"So, I guess the old cat is out of the bag! So excited!!!!!!!!!" O'Donoghue tweeted Friday after the casting news broke.

Suits actor Patrick J. Adams and Limitless star Jake McDorman are to co-star in the series as John Glenn and Alan Shepard respectively.

Actor Leonardo DiCaprio is producing the adaptation of Tom Wolfe's non-fiction book.