Temperatures soar in the height of summer, warping iron tracks and delaying trains. Problems are also caused by trespassers on the line, suspected drug users and an electrocuted pigeon.

Signal problems lead to a restricted service during rush hour, which causes severe congestion at the station. Twenty four hours later, the same signal causes more problems, which leads to the complete suspension of the line. And a team of engineers try to replace 60 feet of track in just four hours.