For those unfamiliar, the Biggles books were a long-running series of boys own style adventures about a WW1 British pilot (the series ran long enough to take in WW2, post-war secret service adventures and even a series of Kiplingesque prequels about his childhood in India), and terrific fun they were too. The movie was in development for more than a decade (at one point a hideously miscast Dudley Moore was mooted for the lead after hitting it big in 10) and the finished film looks like they finally just decided to make something, anything because they'd spent so much money in development.
The end result is the biggest misconceived fiasco of a potential franchise until Working Title's 2004 Thunderbirds came along and turned a weekly sci-fi disaster movie series into a bad kiddie flick. So, to appeal to an audience with no interest in the series and to alienate anyone who was, the plot centres around an American TV dinner promoter who finds himself traveling back in time to 1917 to help his 'time twin' Biggles destroy a secret German weapon that could help them win the war and change the course of history. If that isn't bad enough, it comes with a woefully wrong score by Stanislas that sounds like a BBC Radiophonic attempt to do New Romantic via Kraftwerk, a complete absence of dogfights, poor action scenes, weak comic relief, lazy direction from John Hough and terrible writing (the 'love' story is related entirely as backstory by one of Biggles' sidekicks). Peter Cushing is fine in his last film role and the film does have one deliriously demented line of dialog - 'Get us out of here before they realize you're not a god, you're just an American!' - but is definitely best avoided by lovers of the books.
At least the original UK DVD from Prism included plenty of extras, but Slam Dunk's reissue drops even those. Poor show, chaps