Animal in dramatic situation, losing tail (4)
I believe the answer is:
stag
'animal' is the definition.
(stag is a kind of animal)
'dramatic situation losing tail' is the wordplay.
'dramatic situation' becomes 'stage' (where drama takes place or is situated).
'losing tail' means to remove the last letter.
'stage' with its last letter taken off is 'STAG'.
'in' is the link.
(Other definitions for stag that I've seen before include "One who speculates" , "Male at party?" , "Hunted animal" , "This party is for men only" , "A fully-grown male deer" .)