When Dr. Pratt is caught bringing a gun into the emergency room, Dr. Carter feels compelled to defend him -- but his colleague's erratic behavior makes even Carter have second thoughts. Meanwhile Dr. Weaver hopes to keep her pregnancy a secret, but physical complications might compromise her plans. Elsewhere, Dr. Lewis keeps a wary eye on a self-destructive patient who admits to molesting young boys; a guilt-stricken Dr. Kovac is warned by Dr. Romano not to admit his fault to the grieving relative of a patient he treated; Dr. Chen treats some student math whizzes who overdosed on Ritalin; and Dr. Gallant confronts a scheming young wife who has designs for her dying husband.