If you've ever watched Horrible Histories you'll know that the Egyptians had some strange ways to bury important people.
Mummification involved all the organs being taken out and carefully looked after - except for the heart, which is needed to get into the afterlife.
Joe's been to see 'Jed', a mysterious 3,000-year-old mummy with a difference.
Jed, who was an important priest, is missing his heart - and that's left historians a little bit puzzled.
Horrible Histories clip courtesy of Lion Television.