Sally Magnusson presents a series that goes behind the scenes at police forces' Missing Persons Units across the UK and looks at cases from the National Missing Persons Helpline. A young Cambridge graduate with great prospects, Robbie Carroll loved the finer things in life. His ambition was to be a university professor but his career didn’t take off. After the death of his mother he found it difficult to cope. He was living in Stamford, Lincolnshire and becoming increasingly isolated. His disappearance was discovered when a friend went round to his house - the door was unlocked and his computer had been left on. It was as if he’d just popped out to run an errand and would return any time. Alice Kpongbosu is an elderly lady with advanced dementia who needs constant supervision. She has wandered out onto the London streets and now her son is searching for her. Worried his mother won’t remember who she is or where she lives, he has reported her missing to the police.