Profile for chelspires

At some point in the first act, I believe it's the first time Alex (Tom) runs up the stairs, is something intentionally knocked off to on to the floor? There's a pause as Alex looks at it and then continues, and another pause and stare before he walks off stage. I couldn't recall if he ever mentions what the item is--what is it? Based on the pace of this particular play, Tom's reaction was so well acted, but it just seemed so random. I've also considered maybe it's to foreshadow the climax of...