Attack Of The Invisible Knights! And Robin's Unassisted Triple Play! "Attack of the Invisible Knights" is about the dynamic duo solving the mystery of the Gotham Museum's 'Black Opals' aka medieval Knights Armour that appears to be ghostly. The second story, "Robin's unassisted Triple Play", is when Batman is called away to help the JLA and Robin tries to capture thieves alone but uses a the noise of a rock breaking a window to make it seem that bBtman is outside the building. He then captures the thieves by himself.