How to get one bloc to update another on the same page

OK, lets say I have a news page with a main block that contains the current story and a column of stories on the right hand side. I would like to be able to click on any of the stories and the expanded story will replace what is in the main bloc without leaving the page. I hope this is clear… any help would be great, thanks

Working on this…

as in you are working on a plugin?

Yes. A custom Bric.