Crooked evil leer causing alarm (8)
I believe the answer is:
reveille
'alarm' is the definition.
(thesaurus)
'crooked evil leer' is the wordplay.
'crooked' indicates an anagram.
'evil'+'leer'='evilleer'
'evilleer' with letters rearranged gives 'REVEILLE'.
'causing' is the link.
(Other definitions for reveille that I've seen before include "call to start" , "The get-out-of-bed bugle call" , "Summons to get up" , "Early call" , "Wake-up signal" .)