| cloak-and-dagger(adjective, show, full, secret, sly) |
| illicit(adjective, secret, sly, legal, forbidden) |
| latent(adjective, secret, sneaky, latent, stealthy) |
| sly(adjective, dishonest, deceitful, secret, sneaky) |
| underhanded(adjective, dishonest, cunning, deceitful, sneaky) |
| veiled(adjective, secret, private, unknown, hidden) |
| backstairs(adjective, underground, undisclosed) |
| close(adjective, secret, concealment, sneaky, stealthy) |
| dark(adjective, feature, obscure, mysterious, hidden) |
| deceitful(adjective, dishonest, sneaky, insincere, underhanded) |
| occult(noun, adjective, secret, unknown, hidden) |
| quiet(adjective, personal, intriguing, confidential, hush-hush) |
| skulking(adjective, secret, private, hidden, sneak) |
| classified(adjective, close, secret, restricted, personal) |
| inside(adjective, special, intimate, personal, underground) |
| mystical(adjective, secret, unknown, hidden, concealed) |
| reticent(adjective, secret, sneaky, stealthy) |
| shrouded(adjective, secret, unknown, hidden, concealed) |
| sneaking(adjective, dishonest, cunning, deceitful, secret) |
| under wraps(expression, adjective, idiom, adverb, show) |