This WordPress plugin can help you to display IMDb ratings score for a movie on your website. It uses the OMDb API to get needed info. You're able to add it everywhere you want - in your theme, blog post or page.

It could be accomplished just by adding the following code at the place where you want to display the IMDb score:
<?php do_action("display_imdb_score", "[imdb_movie_id]"); ?>
Example:
<?php do_action("display_imdb_score", "tt1264904"); ?>

Just use the following shortcode:
[imdb_score id="imdb_movie_id"]
Example:
[imdb_score id="tt1264904"]