The disappearance of Madeleine McCann from a holiday apartment in Praia da Luz, Portugal, on May 3, 2007, remains one of the most enduring and divisive mysteries of the 21st century. Nearly two decades later, in 2026, the case has surged back into the spotlight thanks to renewed focus on one of its most contentious pieces of evidence: the alerts from specialist cadaver and blood detection dogs.

In August 2007, British handler Martin Grime and his two English Springer Spaniels — Eddie, a cadaver detection dog trained to find the scent of human decomposition, and Keela, a crime scene investigation dog trained exclusively to detect human blood — were brought in at the request of Portuguese authorities. Their findings inside Apartment 5A and the McCanns’ later rental car have fueled intense debate ever since.

Eddie first entered the apartment and alerted behind the sofa in the living room, near the wardrobe in the parents’ bedroom, and even to Madeleine’s favourite soft toy, Cuddle Cat. Keela, brought in separately, independently alerted to the same spot behind the sofa. The dogs’ reactions suggested the presence of cadaver scent and human blood in locations consistent with a small child.

Weeks later, the same dogs were taken to an underground car park containing around 30 vehicles. Eddie walked past every car without reaction until he reached the McCanns’ rented Renault Scenic. He alerted strongly at the driver’s side door. Keela then alerted to the boot area and the glove compartment containing the electronic key card. Crucially, this car was rented 24-25 days after Madeleine vanished, and the family insisted she had never been inside it.

Supporters of the dog evidence, including journalist Sarah Poulton and various former investigators, argue these alerts are compelling. Eddie had an exceptional track record with no verified false positives in over 200 searches. Scientific studies support high accuracy rates for well-trained cadaver dogs, often 90%+. The tandem use of the two dogs served as a built-in control: Eddie detects decomposition scent, Keela confirms blood. Both flagging the same areas independently makes random coincidence unlikely. The car result is particularly striking — out of dozens of vehicles, only the McCanns’ triggered alerts.

Yet the evidence is far from conclusive. Martin Grime himself stated in his official report that dog alerts are investigative tools, not standalone proof, and require forensic corroboration. When samples from the apartment and car were sent to the UK’s Forensic Science Service, results were inconclusive. Blood traces under tiles behind the sofa yielded degraded DNA that could not be definitively matched. The boot sample matched 15 of 19 markers to Madeleine’s profile, but the analyst warned it was too complex for reliable interpretation and could come from multiple family members.

Contamination remains a serious counter-argument. Cadaver scent can linger for years or even decades. Apartment 5A was a high-turnover tourist rental that had housed hundreds of guests. The rental car had been used by others before the McCanns. Kate McCann carried Cuddle Cat everywhere, potentially transferring any residual scent. In other cases, Eddie has correctly alerted to old decomposition unrelated to the current investigation.

The McCanns have always maintained their innocence, suggesting the alerts could stem from prior tragedies in the apartment or innocent explanations like transporting dirty nappies or rubbish in the car boot. Portuguese authorities initially named the parents as arguidos (formal suspects) in 2007 but later dropped the status, citing lack of evidence. The case was later reopened, with German authorities naming Christian Brueckner as the prime suspect in 2020. He remains in prison on other charges, and prosecutors continue to build a case against him.

Despite this, the dog evidence refuses to fade. True crime communities remain split. Some see the alerts as the strongest indication that Madeleine died in the apartment that night, with the parents involved in a cover-up. Others view it as unreliable “junk science” that distracted from a stranger abduction. Forensic limitations — degraded DNA, no body, no smoking gun — mean the dogs’ reactions have never been definitively proven or disproven.

The emotional toll on the McCann family has been immense. Kate and Gerry have continued campaigning, writing books, and cooperating with investigations while raising their twins. Public opinion remains polarised, with accusations of media bias, police mishandling, and conspiracy theories on all sides.

In 2026, as new documentaries and podcasts revisit the case, the cadaver dog chapter stands out as a symbol of everything that makes the mystery so frustrating: tantalising clues that lead nowhere definitive. The dogs did their job. Science followed but fell short. The truth — whether abduction by a predator, tragic accident, or something else — remains locked behind nearly two decades of silence.

Madeleine would be turning 23 this year. Her parents still hope for answers. The dogs alerted. The forensics were inconclusive. The investigation continues. Until a body is found or a confession made, the alerts from Eddie and Keela will keep the world asking the same painful questions: What really happened in Apartment 5A that night?