sentences:  Mr Smith makes an appearance in the two-part "Doctor Who" episode, "The Stolen Earth", along with Sarah Jane and Luke, helping the two of them to contact other past companions such as Captain Jack Harkness (John Barrowman) and Martha Jones (Freema Agyeman).When former Prime Minister Harriet Jones (Penelope Wilton) asks them to help her send a signal to the Doctor, Mr Smith hacks into every telephone line on Earth, allowing the entire world to phone the Doctor – currently using Martha's old mobile phone – simultaneously, thus breaking through the barrier that Davros (Julian Bleach) and the Daleks had erected around Earth.Mr Smith further assists the team in the finale episode, "Journey's End", with the help of K9 and Torchwood Three, by creating a lasso of temporal energy around the TARDIS to tow Earth back to its proper location in space.