Don't Listen to Mom's Cry

On the morning of December 25, 1986, a happy family awaits the return of the father - a doctor called for emergency assistance - to celebrate Christmas in style. When he comes home, he is met with a real nightmare:... two daughters are dead, his wife is injured, and his nine-year-old son Tom is sitting at his father's table with a revolver in hand...
On April 25, 2021, Sharon Sorensen receives a call from the Los Angeles police informing her that Peter Matthews, arrested for the murder of two children and the abduction of a third, is asking her to represent him in court. Until then, Sharon had mostly dealt with divorce cases; there had been no murders in her practice, but curiosity compels her to agree to find out why a man she had never heard of wants her to be his lawyer.
However, Sharon will soon regret this - when during a search of Matthews' home, photographs of the murdered children along with her pictures are discovered, and she realizes that her client is hiding a lot of secrets...
Who is Peter Matthews - and why did he choose Sharon as his lawyer in a case that is impossible to win?