Beware Charlie Dryden

The sixth book in the Charlie Dryden Series.Charlie Dryden and his friends and family love going to the local railway museum. But his convict friend Mr Lambert tries to warn Charlie off going as he knows there is something wrong at the museum. Undeterred Charlie decides to investigate and it's not long before Charlie discovers that something stinks about the drains.But what and can he find the answers in time?