<Tr> <Th> Audio format </Th> <Td> Stereo </Td> </Tr> <Tr> <Th> Original release </Th> <Td> 11 June 2017 (2017 - 06 - 11)--present </Td> </Tr> <P> The Loch (also known as Loch Ness) is a six - part British television drama series, created by screenwriter Stephen Brady, that first broadcast on ITV on 11 June 2017 . The series follows DS Annie Redford (Laura Fraser), a small town police officer with the Scottish Highland Police as she investigates the murder of piano teacher Niall Swift, who is found dead at the bottom of a cliff in the picturesque village of Lochnafoy, Loch Ness . When it becomes apparent that part of Swift's brain has been removed, and a human heart belonging to another victim is found close by, Annie's team realise they are searching for a serial killer . In response, Glasgow based major investigation detective DCI Lauren Quigley (Siobhan Finneran) is brought in to lead the enquiry . </P> <P> Supporting cast includes Don Gilet as psychological profiler Blake Albrighton, John Sessions as Annie's boss DCI Frank Smilie, Gray O'Brien as Alan Redford, Annie's husband, and William Ash as local tourist operator Leighton Thomas . The series was filmed in the summer of 2016 and was shown in full in the Netherlands and Australia before its British broadcast . The Netherlands also released the series on DVD in May 2017, a month before the series premiered in the UK . In both countries, the series was aired under its original title of Loch Ness . The reason for this change of name is unknown but may have been done so as not to confuse viewers expecting a series about the loch's famous reputed inhabitant . </P>

How many episodes in the loch season 1