slow hes star Jack Loden discusses the plot twist involving his character River cartright at the end of the season 4 premiere going back to the slow horses season 3 finale which provided a preview of the upcoming episodes it was hinted that a member of sloh house will be killed but that knowledge contradicted a scene featuring Jackson lamb Gary Oldman the slooh house boss who appeared unconcerned about the news lamb instantly suspects River cartright of Faking his own death in an interview with radio Times magazine Loden discusses River fate in slow horses season 4 which is based on Mick haren's novels the Emmy nominated actor complements the storyline and expresses surprise at Rivers impending death River slow horses season 4 storyline explained Rivers focus in slow horses season 4 is on his grandfather David cartrite Jonathan price a retired MI5 officer who effectively raised him Adam Randall directed the debut episode identity theft which was written by executive producer Will Smith following an explosion that sets up The Season's other primary Story the spotlight shifts to River and Louisa guy Rosland eleazer the couple seem to be headed down a romantic route although they flirt lightly River genuinely invites Louisa to tell her about his grandfather's deteriorating memory and seek advice on what to do she tells him that it is his responsibility to care for his grandfather in the following scene viewers notice that someone has entered David's home he claims to be named River given his mental state the grandfather cannot say for sure but he eventually recognizes it's an Invader and shoots him David quickly knows he has made a major mistake for the remainder of the program Loden is not seen But by the conclusion with lamb learning the truth following a meeting with sish Sask Reeves it's evident what happened David accidentally shot someone though the identity is unknown River then tells his grandfather to shoot the Intruder in the face to disguise his features giving David just enough time to hide while River disappears but given how important Laden is to the slow horses group River won't be gone for long