'Star Trek Into Darkness' was ''terrifying and painful'' to write according to writers Alex Kurtzman and Roberto Orci.
The writers admit they worried about penning a sequel to 2009's hit 'Star Trek' reboot - which starred Chris Pine, Zachary Quinto and Zoe Saldana - because the first movie was so successful and they felt pressure for the follow-up to be just as good.
Orci told BANG Showbiz: ''It was terrifying and painful. The first one was like, 'Oh, no one expects anything. No one's going to go.' This time was like, 'Show us what you can do.' That's why it took us so darn long [to make it].''
Despite the rich history of 'Star Trek' - ranging from previous movies, TV series and books - the writers felt they had creative freedom to write their own interpretation of the story, but concede it's a delicate balance to honour the work that came before them.
Orci added: ''We're bound to the optimism of 'Star Trek', we're bound to the souls of the characters and that's about it. Everything else is fair game and up for grabs as long as it's somehow harmonising or echoing canon.''
'Star Trek Into Darkness' is in cinemas on May 9.