Case File Compendium: Bing An Ben novel volume 4 was written by Rou Bao Bu Chi Rou (Meatbun Doesn't Eat Meat).

He Yu and Xie Qingcheng barely escape a harrowing life-or-death ordeal, but with Xie Qingcheng's darkest secrets now exposed, can they ever return to normal? Xie Qingcheng is determined to try, yet the revelations have given He Yu a new, profound understanding of his doctor—and of his own conflicted feelings.

When Xie Qingcheng's sister, Xie Xue, succumbs to a disturbingly familiar illness, He Yu recognizes its sinister origin. Now, he and Xie Qingcheng must join forces once more to unravel the dark mysteries of RN-13, the illegal miracle drug that shattered both their lives.