Egen

Professor Egen was a human scientist who wanted to use time travel to directly observe humanity's future destiny.

In 1959, despite the government attempting to put an end to his experiments, he succeeded in building a time machine, speeding off fifty years into the future just as soldiers were about to break into the cave he had converted into his laboratory. Finding the skyscraper cities of 2009 and 2109 not to be interesting enough, he sped past the space station cities of 2309 and all the way to humanity's far future, in 3309 and 3359, where he saw that civilisation had collapsed and humanity had turned back into cavemen in the wilderness.

Horrified, he tried to hop forwards more than the thousand-year-per-trip limit built into his machine, and ended up back in what appeared to be 1959, on the very day he started his first attempts at building the time machine. He began to wonder if all of human history was a gigantic time loop. However, as he stepped out of his time machine, it was melted into scrap by an unknown force while a voice resonated into his mind, telling him that humanity was not meant to know its own future and that any human who glimpsed it would have to have his memory of the experience erased. Indeed, by the time he returned to his lab, apparently replacing his slightly younger self, he had forgotten all about the experience, and was all set to start his work on time travel again.

The Fourth Doctor eventually learned of this "time tale", which "quite amused K9". The Doctor reflected was that Egen's problem had been that he "didn't know when to call it a day". (COMIC: Dr. Who's Time Tales)