London, Jan 24  : Keira Knightley has admitted that acting is like a drug for her, only as long as it is going well.

The 28-year-old singer claimed that she loves getting inside somebody's head while acting, adding that for a second between action and cut, there will be a couple of times where it feels absolutely real, Metro. co. uk reported.

Knightley claimed that moment to be magic, where those words are completely your own and if it's going well, you get it twice a day but if it's not, you don't get it at all. (ANI)