Altered Carbon has a setting where minds can be swapped between bodies, if you got the money. It makes the wealthiest virtually immortal. Meths, as in as old as Methusalem. And it creates a whole lot of human suffering as people exploit the various nasty alternative purposes of such tech.

The protagonist is hired/black mailed into investigating the suicide of a Meth who is convinced that is was murder. The man shot himself in the head, triggering his backup to be installed into a clone. Thus missing the memories of the final moments of his life and so convinced that he'd never do this to himself.

It's a wonderful cyber punk film noir story where technology throws the traditional murder mystery for a loop.