This videosha appears to have been made by a kid who was documenting his house for his own kid reasons. Then, unexpectedly, a shadow person seems to cross the scene. This scares the kid and the video ends. It's interesting in that the shadow form maintains its size and shape as it crosses the field of view. If it were a real shadow, its size and shape would have changed as it receded against the objects in the background of the open doorway.