Jackie's life gets a little more complicated because of a security guard and O'Hara's longtime affair comes to light.

Kevin's younger sister Tunie visits after a breakup with her boyfriend; Lenny prepares a surprise romantic picnic for Zoey; two street vendors are brought in after a turf war turns violent; Akalitus fights Catholic bureaucrats over the hospital's chapel.

Mrs. Akalitus is in a holy uproar as workers from the archdiocese remove her religious statues. Meanwhile, a new temp nurse makes his presence known in the ER, and some people don't appreciate it; Coop deals with personal, professional and podiatric problems; and Jackie tries to deal with Kevin playing matchmaker between Eddie and his sister.

A man is admitted with a steak knife sticking out of his chest. Eddie gives Jackie a Cartier bracelet for their one-year anniversary, but she rejects the gift. A baby is left in the nurses’ station and Akalitus takes the infant to her office.

Jackie admits a patient she has treated before. As his condition worsens, Zoey questions whether Jackie did enough to help him on his previous visit. Jackie’s drug use starts to cause spontaneous nose bleeds.

Eddie tells Jackie that he now considers Kevin a real friend and can no longer lie to him; Jackie is remorseful when she learns that O'Hara is looking for a new employer; Akalitus announces that All Saints may get a visit from the First Lady.

Kelly wins over the All Saints staff; Kevin finds pills in a dental floss dispenser; a patient soothes Coop's depression; Jackie pockets drugs.

Jackie accuses Kelly of being inappropriate with two flirty high school girls; Coop begins to let go of childish things; Thor counsels Akalitus on her new phone system and some deeper matters; Jackie is unexpectedly delayed getting to Grace's pageant.

Jackie tries to stay sober and get through probation until Dr. O'Hara has a tempting offer for her. Meanwhile Eddie believes Kevin found out about the affair and Zoey throws a party for her colleagues.

Zoey leads the ER nurses on a walkout. Jackie battles her cravings.

Longtime ER nurse Jackie Peyton bends the rules to bring some good from a patient's senseless death, while concealing her addiction to a pain killer she gets from her boyfriend, the hospital pharmacist.

An elderly patient checks in who has been treating his heart disease with chicken soup; Jackie discusses her daughter's anxiety with Dr. O'Hara; Eddie learns that he is to be replaced by a pill-dispensing machine.

Jackie and Kevin consider enrolling Grace in private school; the stoic Dr. O'Hara must endure the emotional thanks of a boy whose twin brother she saved; Zoey loses a patient for the first time.

Jackie discovers that a new temp nurse is abusing drugs, but when she confronts him, he calls her on hypocrisy; Mrs. Akalitus still has the foundling infant left at the hospital; Coop reveals to Eddie that Jackie has a child.

After the confrontation with Eddie at the end of season one, it’s now a few months later. Jackie has cut ties with Eddie and is determined to dive back in and spend more time with her family. Back at All Saints, she deflects blame about the narcotic shortage and endures Sam, the altered nurse and his newfound sobriety.

Jackie covers for a hung-over O'Hara, while Eddie befriends Kevin and Dr. Coop gets hooked on microblogging.

O'Hara offers financial help, but Jackie and Kevin refuse to take it. Eddie and Kevin's secret friendship is revealed.

Unhappy about Eddie and Kevin's friendship, Jackie asks Eddie to stop spending time with Kevin. A pharmaceutical company rep provides Jackie with drugs.

Coop insults the biggest donor of the hospital while Jackie revisits her affair with Eddie.

Jackie finds a new hiding place for her pills and buries the hatchet with O'Hara, who becomes ER chief; Zoey works her first double shift; Kevin invites Eddie to a backyard barbecue; Jackie must tell more lies to retrieve her misplaced stash.

Jackie runs out of drugs and Dr. Cooper decides to compete with Dr. O'Hara for the E.R. chief position.

Just when Jackie has run out of pills, she runs into a confrontation about the drugs from Oncology that disappeared. Coop tracks down an old girlfriend on Facebook when he decides to start his own family. Heart problems make Zoey revisit her relationship with Lenny.

Following HR's inquiry of the missing drugs, Mrs. Akalitus puts Jackie on probation. Meanwhile, Coop plans his wedding and Jackie's daughter Grace wants to be put on medication for her anxiety disorder.

Worried about her daughter, Jackie leaves rehab early against her therapist's advice and finds that returning to work greatly rattles her nerves, forcing her to struggle to maintain her sobriety; Zoey has second thoughts about her relationship with Lenny; Eddie tells Jackie that he confessed their affair to Kevin.

Jackie's back to using again, but she's doing it differently this time: maintaining a clean and sober cover, going to 12-step meetings - even finding herself a sponsor - all the while getting her drugs from the towel girl at the gym. Meanwhile at All Saints, Zoey finds out that everyone knows about her 'secret' relationship with Prentiss. Season premiere.