The living cells in the epidermis are located in the stratum basale (also known as the stratum germinativum).

Here's why:

* Stratum basale: This is the deepest layer of the epidermis. It's responsible for producing new skin cells through mitosis. These cells are the only ones in the epidermis that are actively dividing and contain living nuclei.

* Upper layers: As cells move upwards through the epidermis, they differentiate and become filled with keratin, a protein that gives skin its strength and waterproof properties. This process leads to the death of the cells in the upper layers.

So, while the epidermis has several layers, only the stratum basale contains living cells.