The six-part documentary, hitting your TV screens from Monday 20 February 2012, will be shown weekly on BBC2 at 9pm.
The crew from Blast! Films, had been filming across the network since February 2011 and spent time with London Underground staff, taking footage of every aspect of what they do: "from our essential asset maintenance to our staff working on stations, trains and in service control. While LU co-operated with the filming in every possible way, this is a completely independent production that sets out to 'show it like it is' on the Underground".
Monday's episode will focus on a major track replacement operation and an eventful weekend at Leicester Square station, alongside other glimpses into the Tube's day to day work.
TfL said "Our staff have contributed to and collaborated with this BBC documentary, which should ensure that it's a fascinating and fair depiction of both their hard work and the challenges they face every day. One not to be missed!"