Prince with a thousand enemies

There was one king, this was his one sin,
You never make a move, 'til you've got something to prove.

Upon a cross, strapped to a lathe,
Young ingenue, escapes unscathed,
You read the part, but you didn't get it,
left "Lancelot" out of the picture credit.

If there's just one line, that springs to mind today,
Your bottom-lit face, hovering in outerspace.

Upon a cross, strapped to a lathe,
Young ingenue, escapes unscathed,
You read your part from your beer-gut heart,
Then you fell to earth, where you became a star.

Each time, I see, your face, remains,
Your beer-gutheart escapes unscathed,
Left Lancelot out of a part,
You married the monster, but not the art.

You fell to earth, but you wanted it back, now.
You slipped at the tracks now, the one with the cross?
And it's all gone bad hasn't it?
Now that you're dead.