Now it's ??? 92, Todesflug and that's not a detective-story, that is spy-novel content!
Which is why I'll throw Alex Rider in there:
Everything is the same until Bob flees from Ramirez into the mines. He falls and Ramirez doesn't follow him inside, instead stands at the entrance with Greystone telling him to shoot Bob. He does, but not really, since the bullet hits the supporting structure. The tunnel colapses and Bob falls unconscious.
He wakes up to a strange boy sitting next to him, claming to be sent here to find out what Greystone is up to. They try to get back to the cell, but just as they want to enter through the trapdoor they hear Greystone telling Justus and Peter that Bob died in the mines, to which Bob nearly lashes out. Then Greystone takes them away.
Alex and Bob make it to the control room where they figure out what Greystone's evil plan is. So, Alex sets up a transmitter that will give MI6 their location.
At the same time Bob finds a camera from outside the building, where Greystone is torturing Peter. He has to hang on a railing above a cliff until either he or Justus tell Greystone whom they work for. Bob is horrified and so is Alex, to whom the same thing has been done during a previous mission.
Enter: Ramirez, who still isn't over the fact that Greystone has made him shoot a boy his own age. Bob and Alex try to get through to him by telling him he'd indirectly be responsible for Peter's death and that he isn't really a murderer. But, what gets him is the revelation that Greystone would have sent him to his death. He calls Greystone telling him it was an emergency and confronts him about this.
Bob and Alex hide, while Greystone confesses he would have risked Ramirez' life. Meanwhile, Peter and Justus manage to lock that other guy in their cell.
Greystone finds the transmitter and also Bob. He gets so angry, that he sends Bob to space instead of Ramirez (and maybe he also shoots Ramirez, who has betrayed him).
Meanwhile, Alex has found and updates Peter and Justus.
They manipulate Greystone into getting Bob back to earth and just as he is about to destroy the compound along with everyone in it, Alex enters with reinforcement (he had fired their light-emergency-firework-things to get the attention of MI6 who had been on their way but had been kind of lost due to the interrupted transmission).
Anyways, everyone is alive and happy (except for Ramirez, but, maybe he does live through it and gets hired by MI6 or something) and the extremely intriguing door to a Three Investigators-Alex Rider crossover universe is opened.
