After taking an impromptu hiatus from RTE1 (poor SKY Box didn't know what to do, so thankfully it changed itself to BBC2's run of the same series), season four returns to the station. Betty is appalled by Sally's increasingly worrying behaviour - and has no qualms about letting her daughter know the extent of her anger. Roger's behaviour threatens the company's chances of securing a new account, and an executive at a rival firm gets under Don's skin. Sterling drama, starring Jon Hamm, January Jones, John Slattery and Kiernan Shipka.