Dictionary:

Janus-faced

  (jā'nəs-fāst')

Hypocritical.

The adjective has 3 meanings:

Meaning #1: having or concerned with polarities or contrasts

Meaning #2: marked by deliberate deceptiveness especially by pretending one set of feelings and acting under the influence of another
  Synonyms: ambidextrous, deceitful, double-dealing, duplicitous, two-faced, double-faced, double-tongued

Meaning #3: having two faces--one looking to the future and one to the past
  Synonym: two-faced