furtive, covert, sneaky, clandestine, illicit, illegal, nefarious, sub rosa, unauthorized, unethical, sly, underhanded, unknowing, discreet, blatant, devious, underhand, conspiratorial, deceitful, stealthy, unseemly, sleazy, backdoor, indiscreet, overt, disguised, shameless, unsavory, deliberate, secretive, sinister, unwitting, flagrante delicto, unsuspecting, hanky panky, voyeuristic, insidious, brazen, subversive, secret, ungentlemanly, indecorous, untoward, hasty, crass, indiscrete, circumvention, scandalous, unlawful, backstairs, fraudulent, reprehensible, titillating, subliminal, quid pro quo, unauthorised, inadvertent, corruptive, contemptible, contraband, obscene, dubious, witting, ritualised, mossad, subtle, snoopy, unwholesome, anticonstitutional, predatory, paranoic, shady, improper, pernicious, clumsy, salacious, extralegal, perfidious, perverse, passive, dilettantish, unscrupulous, unsuspicious, undignified, forcible, backroom, shameful, inappropriate, tawdrier, panoptic, collusive, pornographic, dirty tricks, purported, disreputable, traitorous, dishonest, nefariousness, injurious, instigative, duplicitous, malicious, unsanctioned, concerted, haphazard, purposeful, unprofessional, effortful, ritualistic, wasteful, hurried, counterproductive

leaker, sneakily, surreptitiously

cloak-and-dagger, concealed, hole-and-corner, hugger-mugger, hush-hush, lurking, on the quiet, skulking, sneak, undercover, underground