During the early parts of Season 2 of “The Flash,” there was a short meeting between Barry Allen and Jay Garrick, who play The Flash and Golden Age Flash, respectively.
Jay Garrick from Earth 2 arrived in Central City at the start of Season 2 following his defeat at the hands of Zoom.
He initially came as a mysterious figure who arrived in Central City to warn Barry Allen and Team Flash of an impending danger that he alone cannot hope to stop, which they learned eventually to be Zoom.
In addition, Jay Garrick was summoned to the S.T.A.R. Labs in an urgent matter from Harrison Wells. It turned out that Wells wanted him at the laboratory because he wanted to make Garrick his guinea pig for an experiment to make speedsters run even faster.
Apparently, Wells wanted to try it on to Garrick first because Barry needed all the help he can get to fight and defeat Zoom. Initially, Jay had second-thoughts about it but because of some life-threatening moments on him and Team Flash, he finally relented to the wish of Wells.
The serum worked as viewers found out and Barry Allen turned out to be faster than ever. In fact, he was able to use his new power to his advantage during the fall finale of the TV series.