Emily Mortimer was baffled to be asked to open her ''sleepy eye'' when filming 'The Ghost and the Darkness'.

The 48-year-old actress starred alongside Val Kilmer in the 1996 historical adventure which marked one of her first movie roles but recalled being left perplexed by director Stephen Hopkins' request for her to open her eye, something she couldn't do.

In an interview with Collider, Emily recalled: ''I remember my first day on that job; I was in Africa and it was all about man-eating lions in Africa, and I'd arrived and I had walked onto this set full of thousands of extras and I had to be standing there with my sort of baby and having come to meet Val Kilmer, and it was quite overwhelming.

''And I remember the director coming up to me after my first take and saying, 'That was really good. You did really well. Well done. But you've got a slightly sleepy left eye. So could you just try and open it a little bit?' ''

The 'Relic' star explained how she admitted that her eyes were ''weird'' but soon realised she didn't have a clue how to make her eyes the same size.

Emily explained: ''I was like, 'OK, yeah, sure. Definitely. Of course. No, no, no. Absolutely. I know really well, yeah, completely. Yeah, I do. I know. I do have slightly weird eyes.

''And so he went off and I was left there thinking, 'Wait. I don't know how to open my sleepy eye! I don't know how to do that so I'm gonna have to maybe close the other eye a little bit to make it...'

''And then they were saying, 'Turn over! Rolling! Rolling! Turn over,' and all these thousands of extras, and all I was doing was trying to make my eye the same size, and you look at the shot and you know, 'What is that woman doing?'''