Tutankhamun's mummy
Detective Michael R. King and FBI profiler Gregory M. Cooper came together with an actual Egyptologist to form their own theory which was that Tutankhamun was murdered. With the use of forensic evidence and their extensive backgrounds in criminology, they came to the conclusion that he was likely murdered by one of his closest advisors, Ay. Ay did succeed Tutankhamun on the throne, so they used that as the motivation for the murder.
Tutankhamun
Tutankhamun was buried in a tomb that was unusually small considering his status. His death may have occurred unexpectedly, before the completion of a grander royal tomb, causing his mummy to be buried in a tomb intended for someone else. This would preserve the observance of the customary 70 days between death and burial.