dr. todd luckasevic underscored that for the jury. what caused this woman's death was? cyanide poisoning. period. >> reporter: no doubt? >> no doubt. >> reporter: nor was there any doubt, said the prosecutor, as to who poisoned autumn. police discovered the defendant's laptop hidden in an office safe. and inside it a wealth of information that told them bob ferrante had indeed been a very busy researcher in the months before his wife's death. >> dr. ferrante was googling searches concerning cyanide, where to purchase it, how to purchase it, the effects on people. >> reporter: and he didn't stop there. the prosecutor said bob ferrante then made an interesting request to his lab associates, something later relayed to detectives. >> he goes to the purchasing person in the laboratory, and he tells this person that he wants to order a bottle of cyanide. >> reporter: has he ever done that before, detective? >> never. >> reporter: better yet, the detectives explained, the doctor asked for the cyanide to be delivered overnight. and when is all this in relation to autumn's slump