The secret of Roman ruins. Bliton E.

The famous five leaves for a few days on a wild island. But, as it turns out, they are not alone here. Something strange happens at night on the island. Someone is trying to scare them, looking out the window and arranging a fireworks from ghostly lights. What are these people looking for in an abandoned cottage? Why do they want to make the guys get out of here as soon as possible? And how is this persecution related to excavations in the Roman ruins that are ongoing on the island?