I'm now at the point in my second book where Boris (the protagonist) is talking to a man who reveals himself to be Sid (the leader of a new group of antagonists). Earlier in the story, the leader made a deal with Rob (the antagonist of the first story) (he would kill Boris in return for objects of great power for his team); Rob held up his end of the bargain, but Sid considers Boris to be of more use to him alive. To this end, Sid arranges a meeting on his yacht with Rob and Boris. Both Boris and Rob want to destroy each other, and neither party will back down. Seeing an opportunity, Rob attempts to kill both of the others (along with everybody else on the yacht), promising to unlock the controls if the Sid will finish the job. When the two begin to fight, Boris knocks out Sid, saves everyone left on the yacht (including Sid), and the boat completes its high-speed course into a cliff face, resulting in a huge explosion. Rob sees the fire ball and assumes everyone is dead. My problem now is that Sid might side with Boris, but I think I have a way of preventing this, as I need them to be at odds until the closing chapters. How would you continue this plot, to prevent Sid from joining Boris' cause? I'll reveal my intentions in a few days and see if we agree.
Please re-read and fix / confirm your use of protagonist / antagonist in the preamble and question. eg: How would you continue this plot, to prevent the new protagonist from joining the protagonist's cause? Confuses the living snot out of me.
eg 2: Seeing an opportunity, the original protagonist attempts to kill both of the others (along with everybody else on the yacht), promising to unlock the controls if the new antagonist will finish the job. Why are you qualifying the protag as "original" - I get the sense there is only one?
suggestion: summarise the characters as Antag A, Antag B, Protag A (Protag B?) or give them names. It's easy to confuse me, so your other option is to wait for others to answer and ignore my suggestions
