Something just barely catches the edge of Olivia's hearing. She reacts without thinking, spinning toward the noise with her gun raised.

That turns out to be the only thing that saves her from a throwing star to the gut.

It strikes the neck of the canister instead, spitting out a loud hiss as the contents start to depressurize. Instantly, she moves again: "Get down!" she yells -- if someone already knows they're here, stealth won't accomplish anything anymore -- and starts a mad sprint for the tree.