 On 31 March 2020, Nine announced that "Doctor Doctor" has been commissioned for a fifth season.The casting director of "Doctor Doctor" is Kirsty McGregor, who has worked for casting on popular television series, such as "Modern Family" and "Top of the Lake".It was announced in early 2016 that Rodger Corser had received the leading role in the series as heart surgeon, Hugh Knight, before the Nine Network has formally announced the series.