It is not that hot.
On one summer day during the 1976 heatwave in London, Gretta's husband leaves her for good taking with him all their savings in the bank, which brings together all her grown children to sort out the problem at hand. Her family is Irish with all the possible catholic guilt there is. With this kind of plot you would think you will get a heck of family story instead you get a spark less drama with a very dull ending.