An archaeology team have come to St Hope's. They think that there are precious artefacts relating to the Roman Ninth Legion in the ground. The entire legion disappeared without a trace and Toby and Linda, the archaeologists, are intent on finding some evidence of their existence. This poses a problem for the spies because the dig site is located dangerously close to the lift shaft. If the archaeologists keep digging, they will uncover HQ.

Oscar is intent on stopping the dig and with a few helpful gadgets from Frank, the spies keep a close eye on what is going on. One of Frank's gadgets looks like a mouse, but is in fact a camera and is transmitting images from the dig back to HQ. While in HQ, the spies spot something rather sinister - A SKUL communicator. SKUL are at St Hope's - but why? Rose's inquisitive brain decides to get on the trail. It must be something to do with the Roman Ninth Legion and the archaeologists. She enlists the help of her friend Abergavenny Smith, from MI38's archaeology department. He informs them that myth has it that the Ninth Legion was wiped out by an extremely dangerous ancient bioweapon. That must be why SKUL is at St Hope's. Someone involved with the dig must be working for them.

The spies must stop the bioweapon getting into the wrong hands, but it is too late! Toby has unearthed the box and it is starting to decompose - the ancient bioweapon gases are leaking from the box and if the spies don't find an antidote, the whole of St Hope's will be exterminated! Show less