J. Robert Oppenheimer did not “disappear” in the dramatic sense — he became a central figure in the Manhattan Project, then later fell from political favor during the Cold War and spent his final years in relative isolation. He died of cancer in 1967.

What happened to him

Oppenheimer helped lead the scientific effort that developed the first atomic bombs during World War II, but afterward his career was damaged by anti- communist suspicion and a security hearing that led to the loss of his clearance. That hearing was widely seen as devastating and unfair, and he was pushed out of public influence even though he remained active at the Institute for Advanced Study in Princeton.

Later years

In later life, he was recognized again for his contributions and received the Enrico Fermi Award in 1963. He then developed cancer and died in 1967.

If you meant the movie

If you meant the 2023 film Oppenheimer , it tells only part of his life and ends before many of these later events.