Cover dirty path frantically, king passing through (5,5)
I believe the answer is:
third party
'cover' is the definition.
(I've seen this before)
'dirty path frantically king passing through' is the wordplay.
'frantically' indicates an anagram.
'king' becomes 'r' (r is abbreviation for rex).
'passing through' indicates putting letters inside.
'dirty'+'path'='dirtypath'
'dirtypath' with letters rearranged gives 'thirdpaty'.
'thirdpaty' placed around 'r' is 'THIRD-PARTY'.
(Other definitions for third party that I've seen before include "Liberal Democrats?" , "Bystander perhaps" , "Kind of insurance" , "Someone other than the principals" , "Another (uninvolved) person" .)