Be in a dodgy situation — hesitation and neck may be broken (5,2,4,3)
I believe the answer is:
skate on thin ice
'be in a dodgy situation' is the definition.
(to skate on thin ice is to behave dangerously)
'hesitation and neck may be broken' is the wordplay.
'and' means one lot of letters go next to another.
'may be broken' indicates anagramming the letters.
'hesitation'+'neck'='hesitationneck'
'hesitationneck' is an anagram of 'SKATE ON THIN ICE'.
(Other definitions for skate on thin ice that I've seen before include "Behave rashly" , "fish displayed thus might not stay fresh for long" , "Court danger" , "Court trouble" , "feeble attempt to keep fish fresh?" .)