Possible to place some virtual object behind a passthrough layer and some in front?

I am trying to create a mixed reality game and in order to make my environment and scene, I would like to hide some virtual elements behind the passthrough layer and only reveal them after an event happens. Kind of like how the passthrough windows work in Ocean Rift MR where the window into the virtual ocean world is show when a window is drawn by the player. Currently, I can only find information about either overlaying all my virtual object onto the passthrough which is default or the reverse. But there seems to be no easy way have some elements in front and some behind at the same time.