Ghost Bride

Made this animation for a weekly challenge with the topic 'Optical Illusion'. In conjunction with the Hungry Ghost Festival, I took the Chinese tradition of ghost marriages as my story to present the optical illusion. The entire scene is not keyframed (apart from the camera and picture frame tilt). No nodes, no light path trickery, and no compositing were used to create the effect. The illusion is 100% dynamic and can be experienced in Blender's viewport as is with a freely controlled camera. Can you figure it out?

Made in Blender 2.93 and rendered with Eevee.