The best time travel story for my money was the Babylon 5 episode involving Babylon 4. The story unfolds in a way that makes clear that some event which has been part of the story since the beginning actually happened because of something the PC's did. And if they don't do it again, all of reality will pay the price. So it's not about changing history, it's about making sure events turn out the way they already have.
I lampshaded this a long time ago in a Battletech 4100AD game I ran once (think Battletech universe, but with Mekton rules and a combat which plays a lot like Macross,) in which the PC's learn that an ancient alien time experiment machine accidentally broke free of its test mount and bounced all over time. In the process of its 5-minute romp through history, it changed a lot of worlds' histories, including Earth's. If an ancient alien race hadn't been messed with by the broken time machine, it would have invaded Earth around the time of the Napoleonic Wars, and nothing which has happened after would have happened. But they get it revealed to them that there's this fragment of video which shows the PC's boarding the broken machine when it just happens to careen through their little bit of space/time in the near future.
Here's where the lure of time travel and experimentation rears its ugly head: The PC's agreed that the course of events had to be preserved, so they went aboard and started trying to make sure its encounters happened. It was fun trying to make it work, because they started near the wreckage of the vehicles they eventually stole on their trip, used in several fights, and subsequently wrecked. Making the in-progress events match what they discovered at the end was the hard part. But that wasn't the worst.
One of the PC's decided that in order to "preserve the natural flow of events," the machine had to be sabotaged, so that its influence on history would be undone. This, of course, would retroactively kill the game and erase all the PC's. But his character was determined to do it. The other PC's wound up in a running gunfight inside an already-damaged time test device, against a PC who wanted to completely destroy it, even if it meant the extinction of her own race. They eventually subdued her, and took her back following the resolution of the time arc.
But it shows that even the best-laid plan involving time travel can go completely sideways, in ways you can't expect or predict. I just wish time travel tv shows were that entertaining...
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Those who fear the darkness have never seen what the light can do.
I lampshaded this a long time ago in a Battletech 4100AD game I ran once (think Battletech universe, but with Mekton rules and a combat which plays a lot like Macross,) in which the PC's learn that an ancient alien time experiment machine accidentally broke free of its test mount and bounced all over time. In the process of its 5-minute romp through history, it changed a lot of worlds' histories, including Earth's. If an ancient alien race hadn't been messed with by the broken time machine, it would have invaded Earth around the time of the Napoleonic Wars, and nothing which has happened after would have happened. But they get it revealed to them that there's this fragment of video which shows the PC's boarding the broken machine when it just happens to careen through their little bit of space/time in the near future.
Here's where the lure of time travel and experimentation rears its ugly head: The PC's agreed that the course of events had to be preserved, so they went aboard and started trying to make sure its encounters happened. It was fun trying to make it work, because they started near the wreckage of the vehicles they eventually stole on their trip, used in several fights, and subsequently wrecked. Making the in-progress events match what they discovered at the end was the hard part. But that wasn't the worst.
One of the PC's decided that in order to "preserve the natural flow of events," the machine had to be sabotaged, so that its influence on history would be undone. This, of course, would retroactively kill the game and erase all the PC's. But his character was determined to do it. The other PC's wound up in a running gunfight inside an already-damaged time test device, against a PC who wanted to completely destroy it, even if it meant the extinction of her own race. They eventually subdued her, and took her back following the resolution of the time arc.
But it shows that even the best-laid plan involving time travel can go completely sideways, in ways you can't expect or predict. I just wish time travel tv shows were that entertaining...
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Those who fear the darkness have never seen what the light can do.