The first episode of the Channel 4 programme, 24 Hours in Police Custody: Murder in the Woods, looked into the investigation behind the murder, how police struggled to find a lead, Jordan Shepherd's denial in being involved and Sam's mum's heartbreak. Sam was stabbed and assaulted with a baseball bat and his body, which was later found in Hinchingbrooke Country Park having more than 20 separate injuries. The first of a two part series was aired on Monday night at 9pm, with the show following the complex investigation which consumed many working lives within the Major Crime Unit at Cambridgeshire police, based at the headquarters in Huntingdon. At the start of the show, viewers heard how police struggled to find strong leads to solve the case, due to lack of evidence or CCTV footage. Arriving at the scene was DCI Adam Gallop, senior investigating officer for Cambridgeshire police, who said: "I tell you what I am thinking; I am thinking that it feels like an execution." Sam's body was found by a dog walker at about 1.30pm the day after the murder. DCI Gallop said: "Very early stages of any investigation I would always try and get down to the scene of the crime as soon as possible. The first stage is just trying to read it, and understand it, and make sure that it makes sense. "Almost in your brain trying to press the rewind button and trying to figure it out, was he carried, was he dragged was he assaulted elsewhere. "Huntingdon is a small market town so to find a man with stab injuries in the middle of the woods; it is very unusual for that to happen. What is it that we can do to solve this, because I don't want people in Huntingdon fearful they are going to get randomly stabbed in the neck. "We need a breakthrough from somewhere." Despite extensive searches of the park, including by specialist diving teams, the knife used to stab the 20-year-old multiple times was never found, nor was his mobile phone. Tracing Sam's movements from the night of the murder, he is seen with girlfriend Megan Knight on CCTV walking through Huntingdon High Street at around 7pm. This was the last time that he was seen on CCTV. But finding a reasoning for the murder proved challenging for the force. "We have to find a motive somewhere, and hopefully that might lead us towards some suspects, but it feels quite tricky at the moment," said DCI Gallop. But further information led police to believe that Sam had been involved in drug dealing - particularly cannabis - earning on average £2,000 a week. His mum, Grace Groom spoke during the show, calling Sam a "gentle giving young man." She said: "Those who knew Sam, who really knew Sam they will know that he was a really gentle giving young man who would have done anything for his friends. "Two police officers came in the early hours of the morning to tell me that Sam's body had been found, that he was dead. It is really difficult to explain to anybody how you feel and things change almost minute by minute. So I could go from crying, sobbing to being, horribly angry, a real black rage, and then back again. You suspect everybody, and I do mean everybody." It was revealed during the show that Sam Mechewlewski was living with fellow drug dealer, Jordan Shepherd, which later on, led police to Shepherd's arrest. But a teaser for the second part of the show, reveal that a second suspect is also arrested for the murder. Months of hard work from Cambridgeshire police is illustrated throughout the show, showing the extent that officers had to go to to secure a conviction. The second part of the show will be on this evening (Tuesday) at 9pm.