Hi, I was well into modeling a character for a short movie and I ran into into this weird bug: whenever I convert an a poly object into subsurface division (alt+`) it works fine: Before conversion: https://www.student.cs.uwaterloo.ca/~.../3d/help/1.jpg After conversion: https://www.student.cs.uwaterloo.ca/~.../3d/help/2.jpg so far so good. The trouble begins whenever I undo that conversion (using 'z' key), the resulting shape is some sort of mix between poly and sub-d surface: https://www.student.cs.uwaterloo.ca/~.../problems1.jpg a closer look: https://www.student.cs.uwaterloo.ca/~...lems_zoom1.jpg There seems to be some sort of residual cage underneath, you can see it when I move the vertices. That cage seems to be unselectable as well: https://www.student.cs.uwaterloo.ca/~...lems_zoom2.jpg If anyone knows how to fix this, your help is greatly appreciated. I've pretty much stopped all modeling trying to find out how to fix this. Thanks