It’s old-fashioned (quite a lot about God and the US military in Afghanistan, plus a completely unbelievable level of toleration of bizarre employee behaviour on the part of the US Postal Service) - but I am completely hooked. The four main characters, the acting, the long rocky road to pairing up, the sheer cleverness of the letter plots, the laughs and the crying…. I’ve just started series 3 and will be bereft when it ends.