( CNN ) -- Charlie Hunnam did n't drop out of `` Fifty Shades of Grey '' because he did n't want to play the lead , Christian Grey . He dropped out because the timing had him on the verge of a nervous breakdown . `` I would n't have signed up in the first place if I did n't want to do it , '' the `` Sons of Anarchy '' actor , 34 , has said . `` It was a really , really difficult time in my life . '' Hunnam was initially cast in the adaptation along with Dakota Johnson in September 2013 . But by the following month , Hunnam had parted ways with the project , citing scheduling conflicts . That part , the actor now says , is true . Between his work on FX 's `` Sons '' and his commitment to Guillermo del Toro 's 2015 release , `` Crimson Peak , '' there just was n't a lot of room for `` Fifty Shades of Grey '' no matter how badly Hunnam wanted it to work . `` I was going to finish 'Sons ' at like 11 p.m. Friday night , get on the plane Saturday morning to Vancouver for 'Fifty , ' missing the whole first week of rehearsal and start shooting Monday morning , '' Hunnam said . `` And I was going to shoot that film , wrap that on the Wednesday and the following Monday I was going to start shooting 'Crimson Peak ' in Toronto . I just had like ... frankly , something of a nervous breakdown . '' Explaining 'Fifty Shades ' wild success . The intense reaction to the `` Fifty Shades '' casting news did n't help . Fans were particularly livid about Johnson landing the part of naive student Anastasia Steele , but Hunnam also felt the pressure . `` I just said ' I ca n't ' ... to fail on such a grand scale , '' Hunnam recalled. `` 'Fifty 's ' going to be massive ; it 's going to be huge . I really did n't want to fail on such a grand scale , and I just could n't transition from ( 'Sons of Anarchy's ' ) Jax Teller to Christian Grey in 48 hours . I bit off more than I could chew , and it was painful . I loved the character , and I wanted to do it . '' Instead of Hunnam , moviegoers will see relative newcomer Jamie Dornan in the role of Mr. Grey . The film , which recently debuted its first trailer , opens February 13 .
Charlie Hunnam said he had a nervous breakdown over `` Fifty Shades of Grey '' It was the proposed schedule that stressed him out . He said: 'I just couldn't do it.