Merubah localstorage ke object

Gimana Cara mengubah Localstorage ke object gmn y? saya menggunakan json.stringify tapi kok gak ada keynya y

result setelah diolah

["{"Description":"Utang","Nominal":"30000"}", "{"Description":"Bayar Utang","Nominal":"3000"}", "{"Description":"Tes","Nominal":"100"}"]

harusnya

[{"Description":"Utang","Nominal":"30000"}, {"Description":"Bayar Utang","Nominal":"3000"}, {"Description":"Tes","Nominal":"100"}]

ajaxnya

$("#inputInvoice").click(function(){
            var prn = $('#prn').val();
            var nmp = $('#nmp').val();
            var alm = $('#alm').val();
            var usr = $('#usr').val();
            var sts = $('#status option:selected').val();
            var desc = localStorage.invoiceItems;
            // var descz = JSON.stringify(desc);
            // console.log(descz);
            $.ajax({
              type: 'POST',
              url: "inc/functions-ajax.php",
              dataType:"json",
              data: {act:"inputInvoice", prn: prn, nmp: nmp, alm: alm, usr: usr, sts : sts, desc: desc},
              success: function(data) {
                console.log(data);
            }
        });
        });

nah pertanyaan saya gmn sih ngilangi/merubah ["{ ke [{