While it is true that Barry Allen (Grant Gustin) wakes up to an alternate reality and timeline in the upcoming season 3 of "The Flash," he will still have memory of the original timeline he belongs to even if the rest of the people around him have no idea what has happened.

It is no secret that the upcoming "The Flash" season 3 will adapt the comic book storyline "Flashpoint," wherein Barry Allen ends up altering the timeline after he traveled back in time and prevented the death of his mother, which already happened in the season 2 finale of the series.

When "The Flash" returns for its third season, all the events in its first two seasons, including Barry Allen's act of saving his mother, will have already been erased from the minds of the characters, and everything Barry Allen wakes up to is different from the timeline he originally belongs to. For one thing, Barry Allen is no longer Central City's superhero as the city already has his friend Wally West as The Kid Flash (Keiynan Lonsdale). Barry Allen also wakes up to having his mother alive, although in his original timeline, she should have died long time ago.

While everything seems normal to the people around Barry Allen, he knows too well that something is definitely wrong, thanks to his memory of his original timeline still being intact. This will push him to find a way to fix things and restore them to how they should be with the help of other DC superheroes from the other shows on The CW, namely "Arrow," "Legends of Tomorrow," and "Supergirl," which are all set for their respective crossovers to "The Flash."

"The Flash" season 3 will not entirely run on the adaptation of the "Flashpoint" storyline, though, and will only run for a couple of episodes. However, despite this, the altered timeline will leave some repercussions that will remain even if the timeline has already been fixed.

"I think we can state Flashpoint does not last all season long. But there are permanent ramifications," said Gustin in an interview with IMDb at the recently concluded San Diego Comic-Con.

How will Barry Allen fix the altered timeline? What will be the permanent ramifications of the altered timeline? Find out when "The Flash" season 3 begins airing over The CW on Oct. 4.