It is not likely that the hard drive is kaput but more likely that the water got onto the motherboard and caused a short out. Hard drives are sealed against dust, etc.
This may lead to the fuse (if fitted) blowing and you may be able to change it and reboot.
You could open it up and strip down the components to dry out, but this is hot and miss.
Try connecting another monitor to the laptop to rule out display problems. Do display then the thing is kaput.
If kaput then it is possible to recover the files on the drive by placing in into another like laptop...