We unearth the biggest collection of Roman writing tablets in Britain, giving insight into what Roman London was really like. Off the coast of Kent, we dive into the English Channel to complete the biggest marine excavation since the Mary Rose - an 18th-century East India Company ship, packed with silver. Also in Kent, we're on the detective trail to find the very first evidence of Julius Caesar's invasion of Britain - an ancient fort scattered with human skulls and weapons.

• Alice Roberts
• Raksha Dave
• Stuart Prior