It appears that you have resigned from your job and are currently on your notice period. Taking advantage of your foreseeable separation, your manager is loading you with excess work. When you mentioned "criminal," you probably meant to convey that you are working as if you are under "rigorous imprisonment." If my understanding is correct, then you should have titled your post as "Excess Workload During Notice Period" and not the current one.
What is happening to you is unfortunate; however, it is not uncommon per se. Managers, in general, are responsible for motivating their juniors. When a junior submits their resignation, this responsibility of maintaining motivation levels ceases. The manager could be seizing the opportunity to clear some backlog, thus resulting in this excess workload.
At this stage, a smooth separation from your company should be your priority. Therefore, accept the extra work without grumbling. Working heavily for a few more weeks or months may exhaust you, but it should not overwhelm you. Please remember that work efficiency tends to increase with a high volume of work. Simultaneously, consider if there are any delaying tactics you can adopt without upsetting your manager.
Show patience, gentlemen, lest the loss of patience could put you at risk towards the end of your tenure with the current company.
All the best!
Regards, Dinesh Divekar