When her teenage daughter contracts a sexually transmitted disease, an enraged mom blames Lu, since she provided the girl with birth control. Meanwhile, as her 39th birthday draws near, Dana contemplates her choices for having a child of her own; tries to help a couple conceive until the news that the father is HIV-positive gives her pause; and encounters an HIV-positive infant.
Though Peter agrees to be her sperm donor, dealing with all the attorneys proves to be such a headache, Dana considers getting pregnant the old-fashioned way. Meanwhile, stumped by an infant's mysterious ailment, Lu eventually suspects the infant's own mother is the culprit.
Though still wary since she was raped months ago, Lu allows herself to venture out into the dating world when a persistent paramedic tries to bring a little romance into her life. Meanwhile, an unexpected ER patient turns out to be the very person whom Nick and Dana have been seeking and Dana attempts embryo fertilization in between juggling her patients.
When she investigates a suspected case of abuse, Lu finds herself in the middle of a volatile domestic disturbance. Dana, meanwhile, deals with a cancer-stricken teenager who refuses to continue chemotherapy.
In treating an incarcerated patient with cervical cancer, Lu decides to take on the prison system in an attempt to get the inmates proper health care. Hospital executives approach Dana about performing a risky procedure to save the life of an unborn child.
Lu provides care to a homeless woman with epilepsy; in helping a transsexual mother with a custody battle, Dana decides to return to her family and adopted daughters in Virginia.
Though Lu has her own ideas about who should replace Dana, she's surprised to learn that chief of staff Dr. Robert Jackson has already hired former army colonel Dr. Andy Campbell. Soon, the two clash over a case in which a wealthy patient needs a kidney and a poor woman wants to sell her healthy one.
Though she's ready to charge ahead with running the clinic, Andy struggles to balance work with the demands of her two daughters who are having trouble adapting to their new lives. She and Lu butt heads when a junkie patient nearly overdoses.
Lana receives an invitation to pledge; Andy helps Robert research a new drug; a mother struggles to decide whether or not to take her child off life support; a patient of Lu's insists they're sisters.
Andy mobilizes her team to help a former colleague at NASA who's discovered a lump in her breast, from her position in an orbiting space shuttle! Meanwhile, a patient of Lu's returns to the clinic with her baby, and Lu has a nagging suspicion that another patient's ailment may be more than a cold.
While Lu advises Peter on possibly going forward with an accusation against a well-known physician, she and Andy tend to a woman with a rash.
Lu decides whether or not to prescribe pain medications to someone susceptible to addiction; Andy takes care of a hot prospect lawyer.
Andy entertains doubts about her surgical ability. Lu takes care of a pregant patient that's been exposed to chicken pox.
Andy is confounded by a patient's symptoms. Lu must overcome her rape experience in order to help a patient.
One of Lu's patients is a terrorist suspect. Andy takes care of a deaf woman who's arthritic hands could mean an inability to communicate.
Andy goes on reserve status for the Army and aids a ROTC candidate who has Post-Polio Syndrome.
Andy finds out that her father has a very serious illness. Lu takes care of a pregnant woman who may be associated with a couple infant deaths.
The appearance of a patient with the West Nile Virus sends the hospital into a frenzy.
Andy and Lu both have relationship difficulties.
During a passionate disagreement, Andy is hit by her spouse.
Dr. Delgado looks into the mental health of a physician who caters to the less fortunate. Andy tries to help parents who must choose which of their children will receive life-saving treatment.
Lu takes care of a highly volatile patient. Andy tries to cope with her daughter going under the knife.