model looks different in edit mode than in object mode

gangqin.blend (551 KB)
This model looks different in edit mode than in object mode. I don’t know why. Anyone can help?

Something is wrong with the mesh itself. There are lots of weird overlapping faces and bad geometry. It seems to stem from the black keys, but I can’t even select them without a crash in my copy. Where did you get this model?

EDIT: I managed to fix the model by exporting as an OBJ, reimporting, and then ripping and deleting the odd vertex that the black keys all shared. But the model is still a mess. Lots on bad non-manifolds and unclosed n-gons. It will need a lot more work to make it usable.

In some cases cure is to export to some format mesh and import it back into blender.
http://www.pasteall.org/blend/18698