NodeJS catch function error and keep the script running

I am trying to test this decrypt function I copied from another site:

var decrypt = function(mystring, pass, err) {
  if (err) return false;
  var decipher = crypto.createDecipher('aes-256-cbc', pass)
  var dec = decipher.update(mystring,'hex','utf8')
  dec += decipher.final('utf8');
  return dec;
};

If I enter an invalid encrypted value on purpose, an error is thrown and the NodeJS script stops.

Is it possible to return something like 'error occured'; and keep the script running normally ?