Which episode first introduced Jackson Avery?

Jackson Avery was first introduced in the Grey’s Anatomy episode “Invasion.”

“Invasion” is the fifth episode of season 6 and marks the arrival of several Mercy West residents at Seattle Grace. The hospital merger creates immediate tension as the incoming doctors compete with the established residents for patients, procedures, and status. Jackson appears in this group as a surgical resident, played by Jesse Williams.

The episode originally aired on October 15, 2009, and is also notable for introducing April Kepner, played by Sarah Drew. Both characters initially join as recurring figures, but each later becomes central to the series. Jackson’s first appearance therefore launches not only his own long-running story but also the Jackson-April relationship that develops over several seasons.

The title can be confused with other Grey’s Anatomy episode names, including “Great Expectations,” “Time Has Come Today,” and “New History.” Those episodes belong to different points in the show’s timeline. “Invasion” specifically establishes the Mercy West merger and Jackson’s entrance into the Grey’s Anatomy world.