left no stone unturned (verb) comb: search by ransacking
Sinonime: artful, calculating,
cautious,
circumspect,
clandestine, cloaked, conspiratorial,
covert,
crafty*,
creepy*,
cunning, disguised,
elusive,
evasive,
foxy, guileful, hidden, hush-hush,
insidious, masked, scheming, shifty, skulking, slinking,
sly, stealthy, sub-rosa, surreptitious,
tricky*, under wraps, under-the-table, undercover, underhand, underhanded,
wilyAntonime: aboveboard,
forthright, honest, open,
truthful