Help Needed Retrieving Posts With SQL

I want to isolate certain posts within a category using a custom taxonomy (‘trans-front-001’ in this instance). Dealing with the category comes later, but first the following. The nested subquery works — it delivers the IDs of desired posts — but the SQL that wraps it that is meant to produce the posts themselves seems to yield nothing:

<?php
$query = $wpdb->prepare( "SELECT * FROM $wpdb->posts WHERE $wpdb->posts.ID =
(SELECT object_id FROM wp_terms, wp_term_relationships
WHERE wp_terms.term_id = wp_term_relationships.term_taxonomy_id
AND wp_terms.slug='trans-front-001')");

$whichposts = $wpdb->get_results( $query, OBJECT );
?>

Or is the code to which I then deliver these posts a mismatch (working code that was cannibalized from elsehwere — reduced here for concision)):

<?php
if ($whichposts):
   global $post;
   foreach ($whichposts as $post):
      setup_postdata($post); ?>
      <div class="post" id="post-<?php the_ID(); ?>">
         <h2><a href="<?php the_permalink() ?>" rel="bookmark" title="Permanent Link to <?php the_title(); ?>">
         <?php the_title(); ?></a></h2>
      </div>
   <?php endforeach; ?>
 <?php endif; ?>