There are many possible routes to a successful mission. This is
one of them:

At turn 5, Agent Bravo should leave explosives 
At turn 11, Agent Bravo should enter the clock tower
At turn 14, Agent Alpha should find another way up
At turn 15, Agent Charlie should park her car
At turn 17, Agent Alpha should not climb the stairs yet
At turn 20, Agent Alpha should not wear the uniform
At turn 22, Agent Alpha should wait in the stairs
At turn 28, you should detonate the bomb left at turn 5
