Matz & Walter Hill 
Assignment collection [PDF ebook] 

In The Assignment, hitman Frank Kitchen takes a job to eliminate a celebrated fashion designer who’s fallen behind on his debts to the mob. The story takes a savage turn when the victim’s sister, a sociopathic surgeon, decides to punish Frank in a unique way. Abducted and operated on against his will, Frank Kitchen awakens in an altered condition — but still with a hitman’s hunger for revenge…