cloak-and-dagger vs surreptitious

cloak-and-dagger and surreptitious both are adjectives.

Word	Noun	Adjective	Verb	Adverb
cloak-and-dagger	No	Yes	No	No
surreptitious	No	Yes	No	No

As adjectives, cloak-and-dagger and surreptitious are synonyms defined as:

cloak-and-dagger and surreptitious: conducted with or marked by hidden aims or methods

Other synonyms of cloak-and-dagger include clandestine, hole-and-corner, hugger-mugger, hush-hush, secret, undercover, underground.

cloak-and-dagger (adjective)	surreptitious (adjective)
conducted with or marked by hidden aims or methods	marked by quiet and caution and secrecy; taking pains to avoid being observed
	conducted with or marked by hidden aims or methods