Ghostly Underground Mail Rail

Ghostly Underground Mail Rail is a new point and click escape game in which there has just been discovered some tunnels under the city. It seems like many years ago this was a mail rail. There everything seems intact, like it was abandoned and since then no one has ever stepped inside. As there could have been hidden some secret or confidential mails, you were sent to explore are collect everything which can be important. But those tunnels were so long that you got lost. There is only one way to escape, by finding the train pane key. Follow some clues to find it and escape.