and this is a big robbery (like Brinks Matt) What I need is a motive. Why has the money been stolen? I want to include money laundering and use the money for some kind of clandestine operation but not yet sure what. Very brief synopsis of the first five chapters (currently 100-odd pages): Any ideas would be grateful.
Would the clandestine operation be the reason for the robbery? If not, ask yourself: Who are the robbers? What are their background stories? What do they want? What drives them to criminal activity? And so on.
Banks often have safety deposit boxes that can be used to store pretty much anything from money to memories. Perhaps your thieves weren't looking specifically for money but something in one of those boxes. Or maybe the killing of the guard was the motive as you said that he was 'shot dead mercilessly'. He could easily have been the target and not a circumstantial victim - the money was taken so that it looked like a robbery gone bad and not a murder. And, if it was a murder, someone in the bank has something to hide that the guard knew, or could've known, about and they needed the guard to say nothing at all to anyone - dead men tell no tales.
inside job The security guard could have been part of the team, and silenced, so there where less people who knew what really happened. The people who stole, may have been set up, someone else organised the raid, got these people to steal, eventhough, they didnt really know, what they where stealing. another idea, is that they stole the plans for a bigger robbery, and all the material, that was going to be used for it.
