IMDB XRef от Drew Anderson

IMDB XRef finds the people and titles that two or more IMDb pages have in common.

Collect any IMDb pages you're curious about — a film, a TV series, a person's filmography — then hit Find Connections to instantly see every actor, director, writer, or title that appears on all of them. Results show headshots and posters where available and can be filtered to people or titles only.

How it works:
Browse to any IMDb page and click Collect in the toolbar that appears at the bottom-right corner.
Repeat for as many pages as you like. Each page's cast and crew are extracted locally — nothing leaves your browser.
Click Find Connections to open the results panel, which lists every shared entry alphabetically with their IMDb section context (e.g. "Cast · Directed by").

Notes:
On title pages, the toolbar warns when you're viewing a truncated cast list and offers a one-click shortcut to the full credits page.
On filmography pages the extension automatically expands collapsed credit sections before collecting.
All data is stored in your browser's local storage and cleared with the Clear button. No account, no sync, no servers, no spyware.