Blackadder Goes Forth of the characters of Lord Flashheart and Bob from the second series episode "Bells" and also an appearance of the famous flying ace Baron von Richthofen. A plot thread in the third episode "Major Star" involves Blackadder's dislike of the silent film star Charlie Chaplin, whom he finds "as funny as getting an arrow through the neck, and then finding there's a gas bill tied to it". In the fifth episode, the anti-German sentiment in Britain during the war is repeatedly referenced. General Melchett orders Blackadder to find out what is behind the leak in top-secret battle plans and immediately,
Blackadder Goes Forth Wallis and Lee Cornes, who had played minor roles in prior series, appeared briefly again in the fourth series as well. This series of Blackadder was one of the first television programmes in Britain to be made and transmitted with stereo sound, using the NICAM digital system, even though most viewers could only afford, or were only able to receive due to their location, the standard FM mono audio carrier signal. The series was directed by Richard Boden and all interior scenes were shot at BBC Television Centre in front of a live studio audience. Rowan Atkinson recalls that the