- Behind closed doors
- Furtively
- in concealment
- In confidence
- incognito
- Intimately
- On the q.t.
- Cloak and dagger
- Covert
- Declan destined to be hiding a secret
- Furtive
- Furtively
- Secret
- Secret clan destined to miss final
- Act furtively
- Creep
- Creep about; disreputable person
- Creepy person
- Go furtively
- Move furtively
- Prowl
- Creep around
- Creep furtively
- Every other sparrow will roam stealthily
- Go about stealthily
- Hunting, on the ...
- Hunting, the ...
- Lurk