Drug smuggler gets cross (4)
I believe the answer is:
mule
I believe this is a double definition.
'drug smuggler' is the first definition.
(I've seen this before)
'cross' is the second definition.
(thesaurus)
'gets' acts as a link.
(Other definitions for mule that I've seen before include "Hybrid beast" , "Crossbreed" , "Backless slipper" , "Drug smuggler" , "Drug courier; animal" .)