S2, E17: Dr. Choi (Brian Tee) and Dr. Halstead (Nick Gehlfuss) face off over how to treat a patient with stroke symptoms while Dr. Manning (Torrey DeVitto) treats a young boy who fell in the river and watches the family turmoil unfold. Meanwhile, Dr. Rhodes (Collin Donnell) examines the man who saved Dr. Manning's patient and emphasizes the importance of learning from your mistakes to Dr. Reese (Rachel DiPillo). S. Eptha Merkerson, Marlyne Barrett, Yaya DaCosta and Oliver Platt also star.