Sheridan Smith befriends grieving mum who helped catch Grindr serial killer EXCLUSIVE: When Sarah Sak was approached about turning her son's tragic death at hands of serial killer Stephen Port in to a BBC drama, she never imagined suggesting Sheridan play her on screen would spark a new friendship Updated Sarah Sak with Sheridan Smith Get the latest news from across Ireland straight to your inbox every single dayInvalid EmailSomething went wrong, please try again later. Sign up! When you subscribe we will use the information you provide to send you these newsletters. Your information will be used in accordance with ourPrivacy Notice.