In the bottle, perhaps, there's trouble! (3,5)
I believe the answer is:
hot water
'trouble' is the definition.
(to get in hot water is to get in trouble)
'in the bottle perhaps' is the wordplay.
I cannot really understand how this works, but
'the' could be 't' (the is pronounced as a 't' sound in some dialects) and 't' is located in the answer.
'bottle' could be 'water' (water bottle is a kind of bottle) and 'water' is located in the answer.
The remaining letters 'ho' is a valid word which might be clued in a way I don't see.
This explanation may well be incorrect...
'there's' is the link.
Can you help me to learn more?
(Other definitions for hot water that I've seen before include "Trouble - put the kettle on" , "in which Marat fatally found himself" , "Trouble (if you're in it)" , "A state of trouble" , "(Liquid) trouble!" .)