SPOILER WARNING: This article contains major spoilers for "The Wrath of Savitar," the latest episode of "The Flash."
"The Wrath of Savitar" has made its mark on Team Flash. The latest episode of "The Flash" found Wally struggling with visions of Savitar, until ultimately those visions manipulated Wally into falling for Savitar's plan. As a result, Wally traded places with Savitar and was subsequently trapped in the Speed Force.
Over the course of the episode, Wally's visions became stronger and stronger, until he couldn't tell the difference between his hallucinations and reality. As he dealt with his blurred reality, the rest of the team discovered that the Philosopher's Stone hadn't been fully destroyed after all. A small piece fell off in the explosion, and Caitlin squirreled it away in hopes that she could use it to get rid of Killer Frost once and for all. As such, she became "the one who will betray" the team, since she hid this secret from everyone else.
Later on, a discussion with Iris caused Barry to have an epiphany. Savitar was trapped in "eternity," or the Speed Force, and he needed the Philosopher's Stone to get out. Since he didn't have the whole Stone, he was still trapped in the Speed Force. However, though his manipulation of Wally, he convinced Kid Flash to throw the remaining piece of Stone into the Speed Force. In response, the Speed Force sucked Wally in -- and Savitar was able to claw his way out and reenter the physical world.
Savitar then explained to Barry that he needed someone to take his place in the Speed Force. Because he was the one to throw the Stone, Wally ended up as that replacement and -- as Savitar predicted in an earlier -- "suffer[ed] a fate worse than death," as that kind of existence within the Speed Force is extremely painful.
Barry also learned that Savitar used the Flashpoint timeline to his own advantage. Thanks to his knowledge of Flashpoint, Savitar was able to create Kid Flash for the purpose of manipulating his speed, which allowed Savitar's release from the Speed Force. However, Barry wasn't able to glean much more information than that; all Savitar was interested in telling Barry was "worship me" and "I am the future, Flash."
Starring Grant Gustin as the Scarlet Speedster, “The Flash” airs Tuesdays at 8 pm ET/PT on The CW. The series also stars Jesse L. Martin, Tom Cavanagh, Carlos Valdes, Candice Patton, Danielle Panabaker, Keiynan Lonsdale and more.