keith morrison: va special agent nate >>> the a special agent, nate landkammer had martha ann mcclancyion was about to take a sudden turn to evil. he had learned about the suspicious photos sean and mcgavic one found in the computer martha ann had given them . pictures of bob found dead. >> he contacted the u.s. attorney's office and said, i have some information that you might want to know that might be helpful to the investigation. >> i had phone conversations between sean and i. >> nate learned, there had been an investigation into bob mcclancy's death six years earlier. remember, detective travis jones had been called to the house after 911 call placed by chuck. >> i just walked into the residence, just a plant growing in the landscape of the fire. mr. mcclancy appears to be in the fire. >> back then, the detective thought chuck was acting way too calm, was avoiding cpr on his best friend and was staging that's perhaps too convenient, do not resuscitate order. and it turned out the detective had good reason to want to question chuck after he discovered a digital camera inside the b