>> it was a huge bonfire, flames as high as the roof on the edge of the roof on the garage. >> was it all making sense to you? >> looking at the whole picture, absolutely. >> and that picture came into sharper focus when fassbender's team found another clue, teresa's key in avery's bedroom. >> the toyota key, with the fob. connector to it. >> this is huge. >> yes, it's huge. >> especially when the crime lab later found avery's dna on it. it would become a highly controversial clue in this case. the evidence was stacking up against steven avery, and fassbender says that rav4 would later tell investigators one last thing. >> we had tested the hood latch and found dna matching steven on the hood latch. >> fassbender believed avery had some explaining to do. so nine days after teresa's disappearance, he and his partner, mark wiegert brought