Carol goes into labor on the El train. Luka happens upon her and helps her to the ER. She delivers one twin there and is then taken up to Maternity, where she is cared for by OB nurse Abby Lockhart. Dr. Coburn delivers the second twin by emergency c-section. Mark abandons his Thanksgiving dinner at Elizabeth's to be Carol's birthing coach, leaving Elizabeth with his grumpy father and a rather sullen Rachel, who unexpectedly experiences her first menses. In the ER, Luka cares for an old woman who is dying on what happens to be her birthday. Dr. Dave helps Carter with a diagnosis of a very rare disease, and reveals that he went to medical school in Grenada.