Without A Trace (2002) - 4x24 - Crossroads

While investigating the disappearance of a young female former assistant district attorney, Jack and the rest of the team are blindsided when the woman's ex-boyfriend suddenly opens fire on the FBI offices.

When Alan Davis (Priestley), the former boyfriend of the missing Jennifer Nichols, realizes that he's a suspect in her disappearance, he suddenly pummels Jack, grabs Jack's gun and bolts out of the FBI building while firing a hail of bullets. Before and after the shooting, Jack and the team delve into Alan's background and possible motives while also looking into the relevance of Jennifer's mysterious visit to a prisoner the night before she vanished.