Get id from metabox dropdown

the_meta is a very bare-bones method. The return value you’re seeing is raw, unserialized data. WordPress uses PHP serialization to store complex values like Arrays and Objects as a string value. Have a look at get_post_meta:

$guest_id   = get_post_meta( get_the_ID(), 'episode_guestid', true );
$guest_post = get_post( $guest_id[0] );
echo '<pre>';
print_r( $guest_post );

You should see the post you’re looking for. Let me know if that doesn’t work.