C141 38th episode, Broken Sword and the Gate of Heaven (2)

This stone wall looked smooth, but it was actually uneven. There were mechanisms within, and without seeing Yu Lin's movements, the stone wall had somehow moved. It first stuck out, then slowly shifted to both sides, and a large door had appeared.

It was pitch black inside, and although the outside sunlight was just right, the light seemed to have been devoured inside, making no difference