Answer: insecret

AnswerCrossword Clue
INSECRET

Undercover

INSECRET

How backroom deals are conducted

INSECRET

Covertly

INSECRET
Sub rosa
INSECRET
Confidentially
INSECRETClandestinely
INSECRETUnbeknownst to others, bug picks up pair of recruits (2,6)
INSECRETWithout the knowledge of others.
INSECRETOn the quiet
INSECRETOn the sly
INSECRETBehind closed doors
INSECRETBug holds musical note without being obvious about it (2,6)
INSECRETOvertly
INSECRETOn the q.t.
INSECRETHow some lovers meet