reporter: olga litvinenko had a falling-out with her father in 2011. she was then a member of the st. petersburg city parliament, but did not vote the way her father told her to. he then got a court to take away her daughter, who was just a baby at the time. olga fled the country and has not seen her child since. she is willing to testify against her father. olga: i am frightened. they could kill me. i am sure of that. but above all i am a mother fighting for her child. and you can't hold a mother back who is fighting for her child. reporter: back in st. petersburg, dmitry sukharev says he expects the court case will drag on for months. dmitry: we are going to prove that we are right. we are going to unmask those who are corrupt and demand that they be punished accordingly. reporter: sukharev has some degree of protection, as he works for a well-known organization. climate protection. this week takes us to uganda, where just one person in five has access to a steady power supply. firewood is the primary source of energy here. one sustainable alternativ