The Somerton Man was an unidentified man whose body was found on 1 December 1948 on the beach at Somerton Park, a suburb of Adelaide, South Australia. The case is also known after the Persian phrase tamám shud (Persian: تمام شد), meaning "is over" or "is finished", which was printed on a scrap of paper found months later in the fob pocket of the man's trousers. The scrap had been torn from the final page of a copy of Rubaiyat of Omar Khayyám, authored by 12th-century poet Omar Khayyám.

Following a public appeal by police, the book from which the page had been torn was located. On the inside back cover, detectives read through indentations left from previous handwriting: a local telephone number, another unidentified number, and text that resembled a coded message. The text has not been deciphered or interpreted in a way that satisfies authorities on the case.

The case has been considered, since the early stages of the police investigation, "one of Australia's most profound mysteries". There has been intense speculation ever since regarding the identity of the victim, the cause of his death, and the events leading up to it. Public interest in the case remains significant for several reasons: the death occurred at a time of heightened international tensions following the beginning of the Cold War; the apparent involvement of a secret code; the possible use of an undetectable poison; and the inability of authorities to identify the dead man.

On 26 July 2022, Adelaide University professor Derek Abbott, in association with genealogist Colleen M. Fitzpatrick, claimed to have identified the man as Carl "Charles" Webb, an electrical engineer and instrument maker born in 1905, based on genetic genealogy from DNA of the man's hair. South Australia Police and Forensic Science South Australia have not verified the result, but South Australia Police said they were "cautiously optimistic" about it.