On The Flash Season 2 Episode 17, Barry traveled back in time to learn what he could from Harrison Wells/Eobard Thawne.
But was he able to hide his persona from the team the whole time he was there?
Of course not. Barry's best laid plans always have at least a few missteps and this time was no different.
Not only did his former mentor and enemy get suspicious early on, but the tranquilizer for other Barry didn't work well, either.
While he was there, though, he had time to mess with the timeline. Whoops.
And, he was able to put together something special for Iris.
Discover what he did and what he got when you watch The Flash online right here via TV Fanatic.
Carissa Pavlica is the managing editor and a staff writer for TV Fanatic. Follow her on Twitter.