. >> registered nurse steven sagatori had been handling ruin teen blisters and dehydration in the medent. suddenly, dozens of victims now needed his help. >> my first patient was a young man in a wheelchair. we brought him in, got him in a stretcher, and he went right out to the hospital. i went back out to start getting -- to bring the next person in and that's when i saw the stretcher with the physician on one side and an ems coming in and a physician was doing cpr. >> it was 29-year-old krystle campbell. >> he was just a beautiful young girl. she reminded me of my daughter, actually. and her wounds were horrific. you know, we worked very hard on her for a while until it was clear that it was -- it wasn't going to help the situation at all. and at that point we were feeling for a pulse and then the cardiac rhythm on the monitor was such that she was not going to survive and at that point the physician, you know, pronounced her -- said she was dead. >> dead in his arms. >> we just kind of all -- we just let out this gutteral scream, you know. but that was it for that moment because w

still, steven sagatori can't stop thinking about the ones they lost. >> i'm a nurse by profession sort of your profession but you expect it when you're at work. in this case, you know, everyone's out having a good time with a marathon and people are not dead. but i haven't been able to put krystle -- i haven't been able to put that under a box and get it out of my mind right now. i know with time it will but right now i think about it all the time. >>> coming up, drew griffin investigates who was behind the horrific attack and the dramatic manhunt for the suspects. capella university understands rough economic times have led to an increase in clinical depression. drug and alcohol abuse is up. and those dealing with grief don't have access to the professional help they need. when you see these issues, do you want to walk away or step up? with a degree in the field of counseling or psychology from capella university, you'll have the knowledge to make a difference in the lives of others. let's get started at capella.edu [ male announcer ] a car that can actually see like a human, using

still, steven sagatori can't stop thinking about the ones they lost. >> i'm a nurse by profession sodeath is part of what i do for a living, but you expect it when you're at work. in this case, you know, everyone's out having a good time with a marathon and people are now dead. but i haven't been able to put krystle -- i haven't been able to put that on a shelf, under a box and get it out of my mind right now. i know with time it will, but right now i think about it all the time. >> coming up, drew griffin investigates who was behind the horrific attack and the dramatic manhunt for the suspects. morning, brian! love your passat! um. listen, gary. i bought the last one. nice try. says right here you can get one for $199 a month. you can't believe the lame-stream media, gary. they're all gone. maybe i'll get one. [ male announcer ] now everyone's going to want one. you can't have the same car as me, gary! i'm gettin' one. nope! [ male announcer ] volkswagen springtoberfest is here and there's no better time to get a passat. that's the power of german engineering. right now lease one of

still, steven sagatori can't stop thinking about the ones they lost. >> i'm an icu. >> announcer: byfession, so . >> i'm an icu nurse by profession, so you expect death as a part of that, but you expect it when you're at work. in this case, you know, everyone's out having a good time with a marathon and people are not dead. but i haven't been able to put krystle -- i haven't been able to put that in a box and get it out of my mind right now. i know with time it will but right now i think about it all the time. >>> coming up, drew griffin investigates who was behind the horrific attack and the dramatic manhunt for the suspects. are you still sleeping? just wanted to check and make sure that we were on schedule. the first technology of its kind... mom and dad, i have great news. is now providing answers families need. siemens. answers. gives you 1% cash back on all purchases, plus a 50% annual bonus. and everyone but her... no. no! no. ...likes 50% more cash. but i don't give up easy... do you want 50% more cash? yes! yes?! ♪ [ male announcer ] the capital one cash rewards card gives y