There are plenty of ways to do this. The easiest if errors and warnings can be ruled out and the output is small is the backtick operator which is also a similar operator in bash:

my $output = `thing.sh args`;
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If output is extensive, but nevertheless nothing is expected to be printed to *nix channel 2, a pipe can be opened:

my $pid = open my $ph, "thing.sh args |"
  or die $!;
while ( <$ph> ) {
    # process output from thing.sh
}
close $ph;
waitpid $pid, 0;
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If errors and output need separate processing (otherwise can append 2>&1 to the command in option 2), see IPC::Run3 or IPC::Open3, the latter of which takes three filehandles for channels 0 thru 2, the 0 channel needing therefore undef() instead of a filehandle, but otherwise is similar to option 2 above. Finally, if no I/O system communication is required with the process, just pass the commandline to be executed in bash (in this case the autoinvocation with arguments" to the "system" function as a single argument.