Many people with an anxiety disorder do not realize they have a defined, treatable disorder and so anxiety disorders are thought to be underdiagnosed conditions. (Take our anxiety disorder test) John Nettles is defined for an emotional goodbye from his role in the long running ITV detective drama Midsomer Murders. John Nettles has played the lead role of DCI Tom Barnaby for more than 14 years starring in over 80 episodes along with the method confirming his status as one of British Televisions most liked television actors.