Behind the scenes of "The Lazarus Experiment". An episode of Doctor Who just wouldn't be the same without a monster to scare the living daylights out of you! The creation of such a beast is never easy – especially when it's purely computer generated! Confidential is on set throughout this chilling episode, spends some quality time with guest star Mark Gatiss and takes a look at some of the fantastic prosthetic and computer generated monsters created since the series made its welcomed come-back in 2005.