Beseech other guards to reflect (4)
I believe the answer is:
echo
'reflect' is the definition.
(I've seen this in another clue)
'beseech other guards' is the wordplay.
'guards' indicates a hidden word.
'ECHO' can be found hidden inside 'beseech other'.
'to' is the link.
(Other definitions for echo that I've seen before include "Repeated sound" , "Marked by heat" , "Bounced sound" , "Return of sound waves" , "repercussion" .)