#!/usr/bin/perl
use strict;
use warnings;

# use #! from first argument which is a file:
my ($file) = grep -f $_, @ARGV;
# alternative: use #! from last argument:
# my $file = $ARGV[-1];
open my $F, "<", $file or die "Error reading $file: $!";
exec $1, @ARGV if <$F> =~ /^#!(\S+)/;
exit 1;