Chell

Chell (surname unknown) is the protagonist of the majority of the many iterations of Chell's Mind. In the Master Minds canon, she is portrayed by Cyh Scaevola.

First encounter with GLaDOS
Chell, left in stasis in the relaxation centre with the other test subjects, is awoken by GLaDOS and instructed to perform a series of tests typically involving the use of the Aperture Science Handheld Portal Device (Or 'ASHPoD' for short).

Behind the scenes
Chell is unique in the Master Minds as she not only has the largest number of actors portraying her in different Mind Series to that of any other Mind Series protagonist, but also one of the few characters to be portrayed by females. She is also one of the few Mind Series characters to have been portrayed by actors of a different gender from that of the character (having been portrayed by Rychotech, among others).