两面三刀 [- - sān dāo]play a double game; be a double-dealer; be double-faced; be two-faced; carry fire in one hand and water in the other; double cross; double-dealing; double-faced tactics; have two faces; say one thing and do another; use dual tactics:
•¶ 这种非驴非马、两面三刀的人，在我们的队伍中并不是完全没有的。 Such double faced creatures, who are neither fish nor fowl, are not altogether unknown in our ranks.