Thanks very much.
These are the two Queries that work.
The first one seems a bit long(in comparison to the second), but it works
$query = "select mvs_actors.fname,mvs_actors.lname,mvs_actors.id ";
$query .= "from mvs_actors ";
$query .= "left outer ";
$query .= "join mvs_mov_act ";
$query .= "on mvs_actors.id = mvs_mov_act.act_id ";
$query .= "left outer ";
$query .= "join mvs_movies ";
$query .= "on mvs_mov_act.mov_id = mvs_movies.id ";
$query .= "and mvs_movies.id = ".$recordID." ";
$query .= "group by mvs_actors.fname ";
$query .= "having count(mvs_movies.id) = 0 ";
$query = "select mvs_actors.fname,mvs_actors.lname,mvs_actors.id ";
$query .= "from mvs_actors ";
$query .= "inner ";
$query .= "join mvs_mov_act ";
$query .= "on mvs_actors.id = mvs_mov_act.act_id ";
$query .= "and mvs_mov_act.mov_id = ".$recordID." ";