BritBox has announced a slew of new additions in a collection branded 'Out Of This World'.

The streaming service has stealthily been increasing its portfolio in recent months, adding a host of reality TV shows from ITV and Channel 4, Louis Theroux's back catalogue of documentaries and dramas such as Call The Midwife.

The latest additions will include all 17 episodes of the cult '60s mystery drama The Prisoner, all six series of Joanna Lumley sci-fi drama Sapphire & Steel and the original Thunderbirds.

Also arriving are Randall and Hopkirk (Deceased), Dirk Gently, UFO and Gerry Anderson shows Space 1999 and Captain Scarlet & The Mysterons.

The Out Of This World collection will launch on August 20.