Mark is invited to join the staff as an attending physician. Later, he treats a woman with breast cancer, who begs him to kill her. Deb wows Benton with her presentation, leaving Carter in the rear again. A poisonous snake gets loose in the ER. Benton offends Haleh, who spends her day making his job more difficult. The ER gets new crash carts, which are promptly stolen by cardiology.