Transparency and volume perception are important issues in 3-D object perception. We report here a new visual effect in 3-D illusory object perception with binocular viewing, namedpantomime effect', and introduce a new framework of the effect based on three types ofsustaining cues'. We also compare sustaining cues with occlusion cues. In addition, the perception of transparent and volumetrical objects was verified by the experiments using another illusory probe stimulus. It was also found that side sustaining cues played an essential role in volume perception, and the transparency in pantomime effect was different from that in multilayer transparent planes depicted by a random dot stereogram.