Changes abound for the Harpers in Season 4. Susan (ZoÃ« Wanamaker) is looking forward to the birth of her first grandchild, but dreading being a grandmother. Nick (Kris Marshall) is getting fed up with living in his ghastly flat and is trying to think of a way to move back into the family home. The gap between Michael's (Gabriel Thomson) IQ and the rest of the family's seems to be increasing, but so is his libido. And Abi (Siobhan Hayes) is still Abi, only more so! As for perennially put-upon Ben (Robert Lindsay), between his un-wished for tango lessons and the chaos that results from a new arrival in his surgery, being officially declared dead seems the least of his concerns!