OK, so he's not in the office.
But to create these images takes some planning: that can be done in the office!
To show what was involved for this image
watch the video!
The rules are that you can use mirrors, ropes, wires, acrobatics &c, but Photoshop can only be used to remove the ropes. wires etc. Otherwise, it would all be pointless, really, wouldn't it.
Thank you, Toxel, for this introduction to the amazing work of Li Wei.
There are gravity-defying images like this one;
and this one (see, I can't stop!)....