When does NCIS: Sydney return?

The show, a spin-off from JAG, premiered on September 23, 2003, on CBS. It is the third-longest-running scripted, non-animated U.S. primetime TV series currently airing. In 2011, NCIS was voted America's favorite television show in an online poll.
NCIS follows a fictional team of Naval Criminal Investigative Service Major Case Response Team (MCRT) special agents based at the Washington, D.C. field office in Washington Navy Yard. For the first eighteen seasons, the team was led by Leroy Jethro Gibbs.