Tonight ITV are showing Endeavour, about the future Inspector Morse's first murder investigation. Besides having to work as a period crime drama, it risks not measuring up to a much-loved classic.
And on that note, if you say "the prequels" around genre fans you're sure to get a reaction.
Ever run a prequel to an existing game, as a break-from-the-norm session or elsewhere?
It affects action sequences since we know X can't die here (assuming death is on the table in the game anyway) but what other changes does it bring?
What session-friendly things happened in the PCs' or the setting's past?
Will revealing some of their past lessen the mystery of a character's origins and motivations, or will it add depth to their portrayal? And do they want to play the obvious antecedents or something different? (The same question goes for sequel games, naturally.) What would the players really want to explore?
Same system or something else? If it's the same PCs a few years earlier, the same system would be easiest, but if it's a new and different group like the current PCs' parents (or the previous crew of their starship, or the previous holders of their mystical artefacts, etc.) you could change to another system that better evokes a difference in play style. Or a previous edition of the regular game, just to be that bit more meta.
Who do the players play if all the current PCs (or their parents, or whatever) aren't around?
Andy's player in The Watch House once suggested running a session about when the PCs' parents were students, since several of the PCs were the children of Watchers and other in-the-know types. He never actually did it, but it still lead to discussion of who was around, who they'd be played by as de-ageing the grownup actors would be cheating, and which players would be which characters.
Meanwhile, I did once run a prequel to a Vampire: The Masquerade game with one of the same PCs, just with some dots crossed out. Having first appeared in a 40s game, he went on the return in another game set in the 90s (then the present) and then pre-return in the 70s. He didn't have anything kind to say about the cars of the decade.
Of course, a more dramatic prequel for a Vampire game would involve the PCs as mortals, or the players as their normal PCs' sires, for example.