In my UF I have a few scenes in which another species can mind-control/body control the humans (MC's). Instances like taking control of the FMC's arm occur twice in attempts to harm the FMC and another epidsode with the MMC. I wrote these scenes a long time ago. Now I have a problem...

The next novel (not related to the UF) I want to write is entirely about body control/mind control, that's the main premise.

Is this bad to have?

Having pieces of my next novel's premise in my first book?

If it came down to one, I'd rather get rid of the scenes in the UF than get rid of second book entirely.