In 2006 Glasgow was rocked when police discovered the body of a missing 23yearold woman in a church On seeing the brutal way she had been killed the detective superintendent realized she couldnt be the killers only victim He quickly set up a multiforce operation trying to link the killer to other murders What he discovered was one of Scotlands worst serial killers Peter Tobin

Thirteen children suffered lifethreatening collapses in an English hospital Four died With doctors confused by the sudden illness of so many babies and youths police were called in Despite initial medical investigations concluding that the collapses were of natural causes the detective superintendent wouldnt rest until he uncovered the truth There was a killer on the childrens ward

In 2012 fiveyearold April Jones disappeared while playing with friends in a Welsh village Her mothers panicked emergency call led to the biggest search ever in the UK Police officers and hundreds of local residents took part The only solid clue was from a sevenyearold who witnessed April with a man in a gray van The next five days were a frantic race to find the killer

For 17 years a serial attacker struck fear into the elderly community in London raping elderly victims in their own homes The Night Stalker left no fingerprints and very little evidence to go on Detectives had a tough case to crack With the perpetrators unpredictability it was exceptionally difficult for investigators to identify the culprit of these traumatic incidents But they did

In the 80s and 90s there were 200 murders and attacks on sex workers in Britain Police believed there could be a serial killer In 1997 Leicestershire police reopened two unsolved murder cases They had an unexpected DNA hit that matched DNA on one of the murder victims The detectives finally had a suspect Could this attacker be the Midlands Ripper who had evaded capture for two decades

In 2009 an English village was the scene of a brutal murder Police were baffled as to why someone would want to kill this man Apart from a partial footprint the crime scene was clear of all forensic evidence Could the perpetrators have committed an almost perfect murder Detectives were determined to catch the killers and for five months they scoured the country for even the tiniest clue