[Lerc]

Dennis potter wrote an intriguing take on this.

When Potter was dying he wrote Karaoke (which was about a dying writer writing a play entitled Karaoke who discovers his characters actually exist)

This is followed by Cold Lazarus which is set in a dystopian future in a lab working on the cryogenically frozen head of the author from Karaoke.

There is a fairly open question as to how much of Karaoke is a prequel and how much of it is a concurrent experience of the mind being experimented upon.

https://en.wikipedia.org/wiki/Karaoke_(TV_series)

https://en.wikipedia.org/wiki/Cold_Lazarus