Three episodes of this series no longer exist, after an archive purge at the BBC in the 70's saw the destruction of the only known copies. Until recently, there were five missing episodes until an appeal by the BBC called "Treasure Hunt" saw the return of two 16mm film recordings taken from the original video tapes. These recordings had been dumped in a skip outside the Elstree Studios when they were found and taken home by one of the studio staff, 30 years ago. After seeing the 'Treasure Hunt' appeal on TV in 2001, the prints were returned by a friend of the staff member, to whom the prints had been entrusted.
It only took an hour and a half to tape each episode of Dad's Army, though there was a week's rehearsal prior to the actual recording of each episode. In addition, the cast did six weeks location filming in Norfolk and Suffolk for each series, to record exterior scenes; only the scenes in the studio interior sets were taped at TV Centre in London. Sometimes the episodes would be filmed then transmitted a week later.
Arthur Lowe (Captain Mainwaring) had a clause in his contract that stated that he was never to be seen on camera without his trousers
An episode is kept on standby by the BBC for use as an emergency backup program, to be broadcast if a major technical problem prevents normal programs being shown. This came to light on June 20, 2000 when the "Six O'Clock News" (1984) was interrupted by a power failure at the BBC, and an episode of Dad's Army was transmitted in its place.
John Laurie and Arnold Ridley both fought in World War One and both were wounded and invalided out of the army.
Thorley Walters was first offered the role of Captain Mainwaring but declined it as he disliked performing in front of an audience. It was then offered to Jon Pertwee who was unavailable owing to a prior commitment in America. Jack Haig turned down Corporal Jones.
John Laurie was the only cast member to have served in the Home Guard. But Clive Dunn, Arthur Lowe and John Le Mesurier had all served in the regular army during World War Two. John Laurie and Arnold Ridley had also served in the regular Army, in World War One. Of the writers, during World War Two Jimmy Perry served in the Home Guard (he based the show on his experiences), and David Croft served in the ARP (and later served in the regular Army as a Major).
A pilot for a sequel to Dad's Army was recorded for BBC Radio in the late 1970s with Arthur Lowe and 'John le Mesurier' . It was called "It Sticks Out Half a Mile". In it, Mainwaring moves to another seaside resort after the war. He wants a loan with the local bank manager and discovers that the manager is now Wilson. He wants to buy the local pier that has been closed since the war and attempts (with Wilson's help) to buy it off the council. It did not become a radio or TV series but the pilot is sometimes repeated on the digital radio channel BBC7. "It Sticks Out Half A Mile" did become a radio series after Arthur Lowe's death. In this series, which was initially broadcast on BBC Radio 2 in the mid-1980s, Hodges and Pike decide to restore the pier at Framborne-on-Sea and approach Wilson for the loan. The series has been repeated on BBC7.