How to hide the content before the 'read more' line?

Hi,

I have made a portfolio blog for a video maker, on the frontpage I want a screenshot of the video for every post, and when you click on read more, or the title, I want the screen shot to be gone (before the read more line).
And I only want the embedded video and additional info I have put after the read more line in the editor.

So in the list I only want the short story, and when you click read more, I only want the continuing story to be shown.

Is this possible? If so, how?

Roy