Rewrite Rule Help

I run a site that is a combo of vBulletin and WordPress. vB runs the front page and forums, while WP runs the ratings and reviews section of the site.

Now I need a little help with the proper .htaccess mod_rewrite rule to redirect people to the proper links.

Basically, WP was the main site for a long time but I moved it from the root folder to /wp. vBulletin still references a lot of these WP pages and posts as if they were root though. So, example, click on a movie poster on the main page (vB) of the site and it will link to: https://www.domain.com/123456 when I actually need it to link to https://www.domain.com/wp/123456.

So my question is how do I add /wp so the link is proper?