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.
Akhenaten
Similarly, although it is accepted that Akhenaten himself died in Year 17 of his reign, the question of whether Smenkhkare became co-regent perhaps two or three years earlier or enjoyed a brief independent reign is unclear. If Smenkhkare outlived Akhenaten, and became sole pharaoh, he likely ruled Egypt for less than a year. The next successor was Neferneferuaten, a female pharaoh who reigned in Egypt for two years and one month. She was, in turn, probably succeeded by Tutankhaten (later, Tutankhamun), with the country being administered by the chief vizier, and future pharaoh, Ay. Tutankhamun was believed to be a younger brother of Smenkhkare and a son of Akhenaten, and possibly Kiya although one scholar has suggested that Tutankhamun may have been a son of Smenkhkare instead. DNA tests in 2010 indicated Tutankhamun was indeed the son of Akhenaten. It has been suggested that after the death of Akhenaten, Nefertiti reigned with the name of Neferneferuaten but other scholars believe this female ruler was rather Meritaten. The so-called Coregency Stela, found in a tomb in Amarna possibly shows his queen Nefertiti as his coregent, ruling alongside him, but this is not certain as the names have been removed and recarved to show Ankhesenpaaten and Neferneferuaten.