Dyatlov Pass incidentA winter expedition in the Ural Mountains ended with injuries that still invite theories.14 min / Medium Tamam Shud caseAn unidentified man, a scrap of Persian poetry, and one of Australia's strangest cold cases.13 min / Medium Isdal WomanA woman found in Norway with false identities, coded notes, and no confirmed name.12 min / Medium Lead masks caseTwo Brazilian technicians were discovered dead beside cryptic notes and handmade masks.10 min / Easy Hinterkaifeck murdersA remote Bavarian farm, footsteps in the snow, and a crime that was never solved.12 min / Medium Yuba County FiveFive men vanished after a basketball game, leaving behind a trail that never quite fits.14 min / Medium D. B. CooperA skyjacker parachuted into American folklore with ransom money and disappeared.11 min / Easy Roanoke ColonyEngland's early American colony vanished, leaving only a carved word behind.10 min / Easy Oak Island mysteryA treasure hunt, booby-trap legends, and centuries of excavation off Nova Scotia.11 min / Easy Flannan Isles LighthouseThree lighthouse keepers disappeared from a remote Scottish station in 1900.9 min / Easy Disappearance of Maura MurrayA college student crashed on a rural road and vanished before help arrived.12 min / Medium Disappearance of Brian ShafferA medical student entered a bar on camera and was never seen leaving.10 min / Easy Disappearance of Asha DegreeA child left home during a storm, creating one of North Carolina's most haunting cases.11 min / Medium Disappearance of Brandon SwansonA late-night call from a stranded student ended mid-sentence and became a search mystery.10 min / Easy Disappearance of Lars MittankAirport footage shows a traveler suddenly sprinting away before vanishing.8 min / Easy Mary CelesteA merchant ship was found drifting in the Atlantic with its crew gone.10 min / Easy Voynich manuscriptAn illustrated book in an undeciphered script has resisted centuries of analysis.13 min / Medium KryptosA sculpture outside CIA headquarters still contains an unsolved encrypted passage.9 min / Easy Beale ciphersThree ciphertexts supposedly point to buried treasure in Virginia.9 min / Easy Shugborough inscriptionA short sequence of letters on an English monument became a durable code puzzle.8 min / Easy Dorabella CipherComposer Edward Elgar's playful-looking cipher remains unresolved.7 min / Easy Wow! signalA powerful narrowband radio signal from space was observed once and never repeated.10 min / Easy BloopA loud underwater sound sparked speculation before science found a colder explanation.7 min / Easy Green children of WoolpitMedieval villagers described two children with green skin and an unknown language.8 min / Easy Spring-heeled JackVictorian London was captivated by reports of a leaping, clawed attacker.9 min / Easy MothmanA winged figure entered American folklore after sightings near Point Pleasant.8 min / Easy Ourang MedanA ghost ship legend spread through newspapers, radio reports, and maritime rumor.7 min / Easy Axeman of New OrleansA serial killer sent a city into panic with attacks and a bizarre jazz demand.10 min / Medium Zodiac KillerA serial killer taunted newspapers with letters, symbols, and partially solved ciphers.14 min / Deep Princes in the TowerTwo young heirs disappeared inside the Tower of London, altering English history.10 min / Medium Disappearance of the Beaumont childrenThree siblings vanished from an Adelaide beach in 1966, reshaping how Australia thought about child safety.12 min / Medium Sodder children disappearanceFive children were unaccounted for after a 1945 house fire, and their family never accepted the official conclusion.11 min / Medium Disappearance of Frederick ValentichA young pilot reported an unknown aircraft over the Bass Strait before his radio transmission ended.9 min / Easy Isabella Stewart Gardner Museum theftThieves posing as police removed thirteen artworks from a Boston museum, leaving empty frames and unanswered questions.11 min / Medium Lost Dutchman's Gold MineA legendary mine in Arizona's Superstition Mountains has drawn treasure hunters, maps, and fatal expeditions.10 min / Medium Devil's FootprintsAfter an 1855 snowfall, strange hoof-like tracks appeared across miles of the Devon countryside.7 min / Easy Taos HumSome residents around Taos report a persistent low-frequency sound that instruments have struggled to pin down.8 min / Easy Hessdalen lightsUnusual lights over a Norwegian valley have drawn observers, instruments, and competing physical explanations.8 min / Easy MV JoyitaA merchant vessel was found adrift in the South Pacific in 1955 with its passengers and crew missing.9 min / Medium Carroll A. DeeringA five-masted schooner ran aground off North Carolina in 1921 with no crew aboard.8 min / Easy SS BaychimoAn abandoned Arctic cargo ship survived for decades as an elusive ghost ship seen through the ice.7 min / Easy Man in the Iron MaskA guarded prisoner in seventeenth-century France became an enduring puzzle of identity and royal secrecy.9 min / Easy Rohonc CodexA small illustrated manuscript is written in a script that scholars have yet to decipher convincingly.9 min / Medium D'Agapeyeff cipherA challenge cipher printed in a 1939 cryptography book remains unsolved after its creator forgot the method.8 min / Medium