Leak from bathroom cubicle

I have noticed staining at the side of the bathroom cubicle, I have found a couple of tiles at the bottom are loose also some of the grout is cracked.

I am thinking of chipping the grout away and letting it dry for a few days then re-grouting. Would this work or do i need to do more?

Use a hairdryer to get it nice and dry.. Care always with water and electrics but it does a grand job.