It's the conclusion we've been waiting for over the past few weeks: what exactly happened to Carole Packman – the 40-year-old mother who has been missing since 1985?
Dubbed as the British version of Making A Murderer, The Investigator comes to an end with the detective pondering whether Packman's home could be a crime scene.
Though the police conducted a thorough search of the property thirty years ago – the police did not dig up the garden – so Williams-Thomas and his forensic team search for traces of the body.
He also receives a series of letters from Packman's husband Russell, who has been serving life in prison for her murder, whereby he makes a string of astonishing claims. But as his investigation comes to an end, the detective reveals to the victim's daughter Sam – who sparked the new enquiry – what he believes happened to her mother three decades ago.
The four-parter has gripped the nation – viewers have been on the edge of their seats as Williams-Thomas probes the disappearance of the 40-year-old working mother with the help of dramatic re-enactments. With the huge build-up in the episodes thus far, it would be a tad disappointing if the ending was anything but explosive.
As a former cop who was on the original case comes forward and tells Williams-Thomas that he believes it is plausible that Russell burned Carole's body, we're almost certain he'll get to the bottom of it – along with a few unsuspected twists.
The show has garnered a positive response, with many viewers praising it via social media sharing site Twitter. One user wrote: Amazing how @mwilliamsthomas picks at old evidence and finds new info, he makes investigating look so easy! Excited for the final episode," while another put: "Need to sleeeepppp but need to find out what happened to Carole Packman before I go to bed. #the investigator #itv."
Watch The Investigator: A British Crime story on Netflix now.