Unfocused Photo

[Billz]

Is there a way to sharpen the focus of a picture that has already been taken?

A friend and I recently got to meet Tom Baker (the 4th Doctor, Doctor Who) in London.
My picture came out really well, while hers came out unfocused.

Not to the point where it's completely unviewable, but it is noticable.
I figured that I'd ask experts with Photoshop, as most of you have used the software extensively, while I don't even have the software to try for myself.

I wouldn't be asking if it weren't important.

Sorry if this is in the wrong section.

[Vortex]

If you get the trial for Lightroom, you may be able to use the sharpen options, along with a few passes of the brush with sharpness turned to full. May not be perfect, though. Sharpening tools can only do so much.

No idea about photoshop, haven't used it for ages.

[WileyCoyote]

If the original picture has motion/camera blur/unfocused, there is little you can do to fix it. That's why you try to take as many pictures as possible than just one.

[Billz]

Is there nothing else that can be done? 

[Vortex]

Short of a working TARDIS? No, unfortunately.