Who has agency here?
When you answer this question, you’ll have to reveal anyone lying in wait or lurking in the shadows, or let them go as someone who cannot or will not affect what might happen here. So this question gives everyone a complete list of the important actors at present, and what gives them agency or power at the present moment. This can change later as the scene unfolds — drama usually involves the sudden and unexpected shifting of agency, moment-by-moment — but give an honest and comprehensive accounting of everyone with agency on the scene at the moment that someone asks this question, including those that you might have previously hidden.