I'm afraid that I don't have the time to stop and explain this code, but it might get you started.

#!/usr/bin/perl -w
use strict;

my @films;
{
  local $/ = '* ';

  @films = <DATA>;
  chomp @films;
}

shift @films;

foreach (@films) {
  my ($header, $data) = split /\n/, $_, 2;

  if (my ($movie, $show)
        = $header =~ /Movie="(\w+)"\s+show=(\d+)/) {
    my @nums = grep { $_ >= 20 } $data =~ /(\d\d)/g;

    my $tot;
    $tot += $_ foreach @nums;

    print "$movie\t$show\t$tot\n";
  } else {
    print "Invalid Record: $_\n";
  }
}

__END__
* Movie="ABC" show=4
10 20 30 14 90 30
21 13 11 10 09 23
22 05 22 15 19 20

* Movie="XYZ" show=4
10 20 30 14 90 30
21 13 11 10 09 23
22 05 22 15 19 10
[download]

--
<http://www.dave.org.uk>

"The first rule of Perl club is you don't talk about Perl club."