in the know β to perceive or understand as fact or truth; to apprehend clearly and with certainty: I know the situation fully.
inside β on the inner side or part of; within: inside the circle; inside the envelope.
knowing β affecting, implying, or deliberately revealing shrewd knowledge of secret or private information: a knowing glance.
on the inside β in a position allowing access to secret information, special advantage or favor, etc.
on top of β the highest or loftiest point or part of anything; apex; summit. Synonyms: zenith, acme, peak, pinnacle, vertex. Antonyms: bottom, base, foot, lowest point.
perspicacious β having keen mental perception and understanding; discerning: to exhibit perspicacious judgment.
piercing β loud or shrill, as the quality of a voice.
profound β penetrating or entering deeply into subjects of thought or knowledge; having deep insight or understanding: a profound thinker.
sagacious β having or showing acute mental discernment and keen practical sense; shrewd: a sagacious lawyer.
savvy β experienced, knowledgable, and well-informed; shrewd (often used in combination): consumers who are savvy about prices; a tech-savvy entrepreneur.
shark β a person who preys greedily on others, as by cheating or usury.
slippery β tending or liable to cause slipping or sliding, as ice, oil, a wet surface, etc.: a slippery road.
smooth β free from projections or unevenness of surface; not rough: smooth wood; a smooth road.
ear-piercing β extremely harsh and irritating to the ear: ear-piercing noise.
high β having a great or considerable extent or reach upward or vertically; lofty; tall: a high wall.
metallic β of, relating to, or consisting of metal.
clever β Someone who is clever is intelligent and able to understand things easily or plan things well.
intelligent β having good understanding or a high mental capacity; quick to comprehend, as persons or animals: an intelligent student.
astute β If you describe someone as astute, you think they show an understanding of behaviour and situations, and are skilful at using this knowledge to their own advantage.
cagey β If you say that someone is being cagey about something, you mean that you think they are deliberately not giving you much information or expressing an opinion about it.
canny β A canny person is clever and able to think quickly. You can also describe a person's behaviour as canny.
crafty β If you describe someone as crafty, you mean that they achieve what they want in a clever way, often by deceiving people.
farsighted β seeing objects at a distance more clearly than those near at hand; hyperopic.
ingenious β characterized by cleverness or originality of invention or construction: an ingenious machine.
judicious β using or showing judgment as to action or practical expediency; discreet, prudent, or politic: judicious use of one's money.