How can you make a link work after the user logs in?

Hi! I want to be able to have a link to an article of page that is only visible to a logged in user. But the link exists outside of the site, so when you click on the link you are prompted to login. BUT after you log in you are sent to whatever your main page is and not the actual link. Is there a plugin or some code that can be used?
Hope someone can help. Thanks!