Leo is particularly affected by the unit's search for a missing girl. Meanwhile, Angela discovers more about the relationship between her mother and her boss.

Investigating the disappearance of an opera singer, Angela finds a link between the missing star and a married politician. Meanwhile, Dozer enlists her brother in preparing a surprise birthday party.

Investigating the murder of an old friend of Leo's who was working undercover, Angela suspects that the man was a dishonest cop. Meanwhile, she has to decide what to do in her relationship with Dylan, who has disappeared.

The team goes into action to help rescue Dozer, whose flight to Los Angeles has been hijacked. Meanwhile, Angela encounters her former boyfriend Peter, and finds out that her mother once had breast cancer.

The team investigates a millionaire whose wife has disappeared, and who is suspected of killing her. On the personal front, Angela goes to visit her father in prison for the first time in over ten years, but still has trouble letting her guard down about her past with her new boyfriend.

Angela arranges for her brother Jerry to meet her boyfriend Dylan, but things are interrupted by a shooting involving an unexpected visitor from her past. Leo and Dozer hunt for the gunman with their only clue being the code word "bluebird," a reference to her first case with the FBI. Meanwhile, flashbacks reveal how Angela was recruited to join the bureau.

The team tries to derail a father-and-son crime team's plan to rob a sports arena. Meanwhile, Angela finds out that her dying mother could survive if she gets a bone-marrow transplant.

Angela goes undercover as a high school substitute teacher to investigate a series of drug overdoses among the students. Meanwhile, she struggles to make sense of a secret meeting she witnessed between her boss and her imprisoned mother.

When a deadly virus is stolen from a laboratory, the team has less than 24 hours to stop a terrorist from letting it loose on the general public. Meanwhile, Angela's brother Jerry shows up with new evidence that their parents were imprisoned unjustly.

Angela decides to ignore her difficulties with her brother and work together to learn the truth about what happened to their parents.

While tracking down stolen photographic artwork, the team encounters a dangerous assassin thought to be long dead. Meanhile, Angela has another quarrel with her brother Jerry that almost brings their relationship to the breaking point.

Angela's team is stymied in their investigation of a wealthy socialite suspected of murdering an intruder, when he takes refuge in a church. Meanwhile, Angela's brother talks her into paying a visit to the mother she hasn't seen in years, who is dying.

Angela is a bridesmaid at the wedding of her closest friend from college, but has to keep leaving to investigate death threats to a well-known news anchor. Meanwhile, Angela asks Dozer to track down her ne'er-do-well younger brother.