Birth name: Tuthmosis ("Born of the God Thoth")
Throne name: Menkheperure ("Everlasting are the Manifestations of Re")
Rule: 1419 - 1386 BC (8th king of the 18th dynasty, New Kingdom)
Noteworthy relatives: Amenhotep II (father), Tuthmosis III (grandfather), Amenhotep III (son)
By the time Tuthmosis IV became pharaoh, the Great Sphinx in front of Khafre's pyramid at Giza was already more than 1,000 years old and was buried up to its neck in the shifting sands of the desert. There had been many attempts to dig it up— some successful, some not (it's unburied now, of course, and has been so since 1926). The first person to clear away the sand was Tuthmosis IV. He claimed that he was out hunting in the desert and took a nap in the shadow of the Sphinx's head (which would have been the only part sticking out of the sand). While Tuthmosis was sleeping, the Sphinx came to him in a dream and promised Tuthmosis that he would become pharaoh if he cleared away the sand. Digging started immediately and sure enough Tuthmosis IV became pharaoh in 1419 BC. A carved monument known as the Dream Stele between the Sphinx's paws commemorates the "rescue."
During the New Kingdom, royal tombs were built high in the cliffs of Upper Egypt in a spot commonly called "The Valley of the Kings." The intention was to make the tombs as inaccessible to grave robbers as possible... although they got robbed anyway. Around 1000 BC, a group of priests gathered up all the royal mummies and stored them in two secret "mummy caches" (one near Deir el-Bahari, and the other in the tomb of Tuthmosis IV's father, Amenhotep II) to keep them safe. These hidden royals were nowhere to be found for almost 2,000 years: in 1881, the 40 mummies in the Deir el-Bahari location were found. Then in 1898 the tomb of Amenhotep II with its additional 16 mummies was discovered. This is where Tuthmosis IV was found- in his father's tomb.
Granite bust of Tuthmosis IV. By Carole Raddato from FRANKFURT, Germany (Louvre Museum Uploaded by Marcus Cyron) [CC BY-SA 2.0 (http://creativecommons.org/licenses/by-sa/2.0)], via Wikimedia Commons
Mummy of Tuthmosis IV. By G. Elliot Smith [Public domain], via Wikimedia Commons