Barry Allen's "overconfidence" about taking down Zoom resulted in a tragedy as the speed demon claimed Henry Allen's life in the closing minutes of The Flash season 2 episode 22. The chapter also set up the final race between the speed-demon and the Scarlet Speedster.
In the pre-finale episode titled Invincible, Barry and Star Labs members teamed up to take down the army of meta-humans sent by Zoom, which included Laurel Lance's Earth-2 doppelganger Black Siren.
Cisco Ramon came up with a plan to take down all the "metas" running around Central City at once. With help from Harrison Wells, Cisco built a vibrational technology that takes down everyone from Earth-2 without harming anyone from their Earth.
Their plan worked as all the meta-humans were incapacitated and Barry quickly swept the streets and put them behind the high-security meta-prison in Star Labs. Zoom couldn't not withstand the vibration and transported himself to Earth-2.
With all the "metas" and Zoom gone, the group decided to celebrate their little victory over dinner but things turned deadly as Zoom crashed the party and took Henry Allen with him. The evil speedster took Henry to Barry's childhood home where Nora Allen was killed.
In an emotional father-son moment, Henry told Barry that he is proud of him and that he made him the happiest father, following which Zoom used his vibrating death hand through Henry, even as Barry witnessed the death of his parent once again. Also, Cisco vibed about Earth-2 being split apart as Wally West may have figured out that Barry is the Flash.
Warning: Spoilers ahead
The finale episode is titled The Race of His Life, which will air on 24 May at 8pm EST on The CW. Episode 23 will find Barry racing Zoom, in what would be the Scarlet Speedster's race of his lifetime.
The official synopsis reads as follows:
A promo released for the episode shows Barry at Henry's grave, as he vows to take revenge from Zoom for killing his father. The video also shows Zoom challenging Barry to a race, to see who is the fastest man alive. The promo ends with Barry and Zoom running, in what will culminate in an epic showdown between the two speedsters.