While trying to stop SKUL stealing a valuable data disc, Oscar behaves recklessly and is ordered to stand down by the Head of MI9. Back at HQ, he confronts the Head of MI9 who tells him to stay off duty until he has calmed down. Angry and frustrated, Oscar decides to infiltrate SKUL and bring them down from the inside - on his own. He tells Rose and Carrie to keep quiet about his plan and they reluctantly agree.

When MI9 trace the SKUL agents to a warehouse, Oscar gets there first and persuades their leader Vincent to let him join them. With MI9 approaching, Oscar and Vincent escape. In the process, Oscar drops the signet ring his father - former MI9 super spy Edward Dixon Halliday - gave him before he disappeared eleven years ago. When Rose and Carrie arrive, they spot the ring and realise that Oscar has found SKUL.

When the Grand Master sees Oscar he tells him to prove his loyalty to SKUL by helping them to kidnap the Head of MI9. Meanwhile, Rose and Carrie realise that Oscar is in danger and decide to visit his foster family in the hope of discovering more about his plan. They are shocked to discover that he lives with an MI9 agent, not a family, and more surprised still when they find out that Oscar has been desperately trying to find out what happened to his father. All the evidence suggests that he is dead, but Rose and Carrie spot a lead that Oscar's missed and set out in search of Edward. Show less