Frank London is spy handler of the MI High team and caretaker and St Hearts.
He is a very intelligent man who leads the MI High team. He poses as the St Hearts caretaker, which is why most of the students and staff don't take him seriously and find it hard to believe he went to university. His storeroom is the secret entrance to the MI9 MI High base, deep beneath the school.
He has formed a close friendship with his team, the most meaningful one being with Zoe, a clone who looks up to Frank as a father figure. Frank is skilled in hand to hand combat and defeats The Crime Minister in The Final Endgame, although she was a lackluster enemy.
Stella used to be Frank's girlfriend ten years ago, until she dumped him. They are still close. In Trojan KORPS, it is revealed that he used L.O.V.3.L.Y.S.T.3.L.L.A as his password in the bunker ten years ago. She is still very protective of him. There can be a lot of tension between them and it is revealed that the source of the conflict is when Frank led the final assault on the KORPS base. MI9 suffered terrible losses and Stella blamed Frank for the disaster. In The Final Endgame, when Frank is dying in the reactor core, while trying to stop the overload, Stella goes to help him, knowing that she too would die. She helps him complete the code and then they sit together as they are both dying. They end up fixing what happened ten years ago and Stella realizes it wasn't his fault. They then kiss.
- In The Fall of SKUL, Frank tells Mr Flatley that Zoe is his niece and her old school burnt down.
- In The Fall of SKUL, his relationship with Stella is revealed and it is further hinted throughout the series and discussed in One Flew Over the Budgie's Cage.
- Frank has one an MI9 medal for bravery, shown in One Flew Over the Budgie's Cage.