Harm is sent to Washington, D.C., to join a committee formed to judge the validity of a shocking television report -- that U.S. forces used sarin gas on fellow Americans during the Gulf War. What he uncovers, though, is so unexpected that he can't present it without testimony from a key witness, Sgt. Morrison, who was actually on the mission in question in the Gulf, but has been missing ever since.

Meanwhile, Mac is caught off guard when an old flame, Christopher Ragle suddenly reappears in her life.