>The key that opens all doors.
>The 'Start'.
>What is the Keystone. Re_read carefully. Like a Novel.
A thought;
Keys-tone
Like the tone of a key being hit on a musical device.
My favourite choice would be the cosmic key from "Masters of the Universe" released 1987.
Which funnily enough has "Michael Flynn" as an associate producer. KEK
Whether it be the General Flynn or not is out for debate, although he would of been 26 at the time if my maths is correct.
https://youtu.be/A3jsb9adLfA?t=55