The Mark of the Berserker ( TV story ) The Mark of the Berserker was the fourth story in the second series of " The Sarah Jane Adventures " . It was mainly notable for introducing Clyde Langer ' s mother and father . Although Clyde ' s father was central , the story was unique in being the only one to feature the fathers of all three of the series ' primary child characters : Langer , Jackson and Chandra . It even ended on a soft cliffhanger of Sarah looking at a picture of " her " father , who would appear in the next episode . The story had some other remarkable features . Sarah was absent for much of the proceedings , but depicted in part one as being engaged in comparatively ordinary journalism regarding a hospital scandal . In part two , it was revealed that in fact she was tracking a Travast Polong , the same sort of slug - like creature that would return in " The Wedding of Sarah Jane Smith " . Furthermore , part two was one of only two episodes of the series to credit both Yasmin Paige and Anjli Mohindra , and the only episode of the entire series to show a conversation between Maria and Rani . Barring archive footage and photograph s , it was the final appearance for both Maria and her dad . Synopsis . An alien pendant which gives its wearer the power to control others is stolen from Sarah ' s attic . Luke and Rani enlist the help of Clyde ' s mum to track down Clyde and his father , who has the alien pendant . The chase leads to a terrifying waterside confrontation when the pendant takes control of Paul and begins transforming him . Plot . Part 1 . Sarah is going away for the weekend to track down an alien lifeform and leaves Luke to stay with Clyde and his mother for the weekend . Rani walks by the detention room at school . She witnesses a boy , Jacob West , controlling his teacher and fellow students . He runs into the boy ' s bathroom , drops a strange pendant on the floor and leaves . Rani picks up the pendant and pockets it . On Bannerman Road , Rani and her father , Haresh , are deciding on tea and choose to have a pizza . Rani discovers that Haresh will follow her verbal instructions . She deduce s that the pendant causes people to follow instructions given to them by the pendant ' s wearer . Although she initially has fun with the pendant , when her father offers to die as a result to an idle comment , Rani realises how dangerous it is . The next day , somebody knocks on the door of the Langers ' home . Clyde answers it and finds that his long - lost father , Paul Langer , has turned up . His arrival upsets Clyde and his mum . After an emotional discussion among the three of them , Clyde leaves with his father . During the course of the day , Clyde reveals to his father that he is involved in tackling alien threats . Meanwhile , Rani goes to Sarah ' s attic only to find that Mr Smith has been deactivated while the house is empty . Rani decides to leave the pendant there so no - one will find it . After a talk with her father , she decides to investigate matters herself . She finds Luke , and they go to the school to search for clues . Clyde convinces his father that he is telling the truth by taking him to Sarah ' s attic . Paul finds the pendant that Rani left and puts it in his shirt pocket . Outside , they meet Haresh , who asks them about what they were doing in Sarah ' s house . Paul ends up instructing Haresh to do press - ups and realises it must be due to the pendant . Luke and Rani run up to them . Rani works out what has happened and confronts Paul and Clyde . Paul instructs Clyde to forget who Rani and Luke are . They walk off . Paul finds his hand has a strange blue symbol on it . Part 2 . Clyde and Paul are walking in town . Paul can ' t stop looking at the symbol on his hand . Luke and Rani attempt to contact Sarah , but she is preoccupied trying to pursue an alien called Travast Polong . Meanwhile , Luke and Rani send a picture of the pendant to Maria and her father to investigate , as her father can hack into UNIT . They discover the pendant can cause a symbol known as the mark of the Berserker to appear on one ' s skin . Haresh refuses to stop the press - ups . Paul gets everything he wants for free — including a new car — and uses this to bond with his son . He instructs Clyde to forget about how he left him and his mum when he was young and to forget about his mum . The pendant takes over Paul ' s skin , causing blue veins to appear , and he collapses . He declares himself the Berserker and Clyde his soldier . Sarah appears and Clyde recognises her . She tells him that his mum , Rani and Luke are the most important people in his life when he asks who they are . Clyde and his mum talk Paul through his memories , whilst Sarah shows him a reflection of himself in her handbag mirror and he remembers who he really is . Everyone the Berserker commanded has their commands undone . Clyde tries to get his mum and dad back together , but Paul tells his son that he has made his mum ' s sister pregnant . Clyde tells his father he doesn ' t need him , and not to mess up with this baby . His dad then leaves to return the car and clothes . Clyde tells his mother to forget about the pendant , what she knows about Sarah ' s adventures with her son , and his father , then throws the pendant into the sea . Sarah reveals that her parents died when she was young and she would do anything to see them again . When Clyde is gone , she takes out a picture of her mother and father and rubs her finger over the latter . Story notes . Filming locations . " to be added "