Why do we believe in ghosts — and is there actually any evidence that they exist?In this episode of The Growth Time Machine, Daniel Curtis sits down with Dr Ciarán O’Keeffe, one of Britain’s best-known parapsychologists and a familiar face from Most Haunted and the BBC’s Uncanny, for a fascinating, evidence-led conversation about ghosts, hauntings, mediums, scepticism and the psychology of the paranormal.Ciarán has spent decades studying unusual experiences from the perspective of psychology and parapsychology. Rather than beginning with the assumption that every strange experience is supernatural — or dismissing it automatically — his approach is to ask what the evidence actually tells us.We explore why human beings are so drawn to ghosts, why personal experiences can feel so convincing, whether our desire for an afterlife influences what we believe, and what psychology can tell us about that unmistakable feeling that somewhere is “haunted”.Ciarán also takes us behind the scenes of Most Haunted, discussing how he became involved with the programme, his role as its sceptical voice, the difference between genuine investigation and television entertainment, and the pressure that can exist when millions of viewers are waiting for something paranormal to happen.We discuss Derek Acorah and mediumship, including the psychology of performance, cold reading and why demonstrating a possible alternative explanation is not the same as proving that every medium is using it.Ciarán also explains why some of the most compelling paranormal evidence may not be photographs, recordings or pieces of equipment at all — but the strange and deeply personal experiences reported by ordinary people.And there are cases that have challenged even him.We discuss The Battersea Poltergeist, including one extraordinary eyewitness account that initially left Ciarán struggling to find a satisfactory explanation, as well as his own unexplained experience aboard the SS Great Britain.The conversation also explores grief, the ethics of mediumship, confirmation bias, haunted attractions, ghost hunts, religion, the afterlife and even whether accounts of the resurrected Jesus can be considered through the same psychological framework used when examining other reported apparitions.Dr Ciarán O’Keeffe is a psychologist specialising in parapsychology and investigative psychology. His television, radio and podcast work has included Most Haunted, Uncanny, Uncanny: Cold Cases, Ghost Adventures, Celebrity Ghost Hunt Live, Unexplained: Caught on Camera, Jane Goldman Investigates, Paranormal?, The Battersea Poltergeist and The Witch Farm.He has also contributed to academic research into hauntings, ghostly experiences and paranormal belief, and has written and co-written books including Ghosted! Exploring the Haunting Reality of Paranormal Encounters and Ghost Hunters: A Guide to Investigating the Paranormal.Ciarán also reveals during our conversation that his first sole-authored book, drawing on his case-study approach to paranormal investigation, is due to arrive in autumn 2027.🔗 DR CIARÁN O’KEEFFEAll of Ciarán's current links, social media, research and projects: https://linktr.ee/ciaranokeeffeBuckinghamshire New University profile: https://www.bucks.ac.uk/about-us/our-staff/ciaran-okeeffeScientific research / ResearchGate: https://www.researchgate.net/profile/Ciaran-Okeeffe-2The School of Parapsychology: https://theschoolofparapsychology.company.siteUNCANNY & BBCUncanny — BBC: https://www.bbc.co.uk/sounds/brand/m0010x7cUncanny TV — BBC Two: https://www.bbc.co.uk/programmes/p0ghgpd4The Battersea Poltergeist: https://www.bbc.co.uk/programmes/p0940193The Witch Farm: https://www.bbc.co.uk/programmes/p0d508t8Ciarán is also on Facebook, Instagram, TikTok, X, LinkedIn and YouTube as @ciaranokeeffe — all available through his Linktree above.