Every episode is named after a song. During each episode, you'll be able to hear the song that it's named after.
The scenes in the hospital were filmed in Gartloch Psychiatric Hospital, in Glasgow, before it closed. Many of the extras in these scenes were former patients.
The budget was so tight that director David Blair dubbed his own voice over one of the supporting artists' in order to avoid paying them for a speaking role.
David Tennant was, in his own words, "uninvited" to the BAFTA Awards Ceremony so that Angus Macfadyen's then girlfriend, Catherine Zeta-Jones could take his place.