the leon levy center for biography hosted this event and provided the video. she explains how she discovered klaus fuchs while researching her previous book. a screen spend starts by explaining how she found this by while researching her previous book on nobel physicist. >> so let's go at it. i was asking you why close a few cars. >> i actually got interested in him when i was doing this because i had a lot of family papers, i had huge numbers of letters and diaries. in those, during the late thirties when he was there, he was always showing up in some little piece of paper that i had, he was showing up is very nice person. he took their children out to the movies. he played cards with them. he was in their little music on stumble. people liked him, he was very quiet, very shy but he was a nice person and all of a sudden he was a spy and they were dumbfounded and i came into this information as i did, i did know much about him when i was first working on it. so, at that point as i was writing about him i thought i should find out more about klaus fuchs, he's a