Displaying two posttypes from certain category

Hi,

with query posts I can change the default posts on the homepage. But now I want to add two posttypes. Also this is possible:

$query = new WP_Query( array( 'post_type' => array( 'post', 'page', 'movie', 'book' ) ) );

but what if I want two different posttypes but from each posttypes I want the ones from a certain category.

Does someone knows the answer?