Gary Seven was a character introduced in the Star Trek episode Assignment Earth.
He was portrayed by Robert Lansing.
Seven was a descendant of humans who were taken from Earth several thousand years ago by the Aegis to be trained to serve as agents of the Aegis. He was born in 1932 on an unidentified planet in the Zeta Gamma 537 system. A highly intelligent man, he was trained in multiple languages. By 1968 Seven was a supervisor, and given the code name Supervisor 194.
An alien shapeshifter known as Isis was paired with Seven. She took on the appearance of a black Terran cat, but would assume a humanoid form when required.
In 1968 he and Isis were sent to Earth to determine why the Aegis lost contact with the agents working there. His transporter beam was intercepted by the USS Enterprise. He recognized Spock as a Vulcan right away, confirming to himself that the Enterprise was from the future. Captain James T. Kirk detained him on the Enterprise, but Seven and Isis escaped the Enterprise. Seven found out that the Aegis agents working on the planet had been killed in an apparent auto accident. Working with the young Roberta Lincoln, who had been hired by the agents as a secretary, he was able to prevent mankind from launching a nuclear war by destroying a malfunctioning weapons platform 104 miles above the surface.