two-faced

marked by deliberate deceptiveness especially by pretending one set of feelings and acting under the influence of another

• “she was a deceitful scheming little thing” Israel Zangwill
• “a double-dealing double agent”
• “a double-faced infernal traitor and schemer” W.M.Thackeray

having two faces--one looking to the future and one to the past

• “Janus the two-faced god”