On tonight's episode of "The Flash," Barry found himself inside the speedforce, learning from it, even having conversations with it. Back at S.T.A.R. Labs, Henry Allen attempted to save Jesse's life, as she inexplicably slipped into a coma. Joe and Iris were forced to deal with zombie-metahuman Girder, who was back from the dead, while Wells and Cisco had to find a way to bring Barry back into reality. While Barry was in the speedforce he was forced to deal with losing his speed, the trauma of losing his mom, and the real reason he was gifted with powers. Tonight's episode -- "The Runaway Dinosaur" -- was written by "Thor" screenwriter Zack Stentz and directed by the legendary Kevin Smith. It was a poignant and emotional episode that forced Barry to confront the great loses of his life in order to understand what he had truly gained by becoming The Flash.

The episode kicked off with Team Flash reeling from the apparent death of Barry Allen (Grant Gustin.) Henry Allen (John Wesley Shipp) was beside himself with grief and only moved once he realized Wells' (Tom Cavanagh) daughter Jesse (Violett Beane) and Joe's (Jesse L. Martin) son Wally (Keiynan Lonsdale) needed medical attention. Wally turned out to be OK, but Jesse was unconscious. While she was being treated, Cisco (Carlos Valdes) picked up Barry's melted suit and vibed that Barry wasn't dead -- he was actually inside the living speedforce. While this gave the team hope, they were interrupted by the return of the metahuman Girder (Greg Finely.) With Girder threatening S.T.A.R. Labs, the team had to split up: Henry stayed to treat Jesse, Wally went home, Wells and Cisco began working on the speedforce interface, and Joe and Iris (Candice Patton) led Girder away from the labs.

Barry then found himself back in his own room from when he was a kid. As he descended the stairs he noticed a familiar face -- Joe West -- investigating the crime of his mother's death. Unfortunately this wasn't Joe West, this was the speedforce, personifying itself using people that Barry trusted and loved. Throughout Barry's time in the speedforce he spoke with four people: Joe West, Iris West, Henry Allen, and his mom Nora Allen (Michelle Harrison.) Each one of them had a lesson to teach Barry. These personifications were like the ghosts of Christmas past, present, and future in Charles Dickens' novel "A Christmas Carol." They were all designed to reveal something to Barry, to help him get his powers back, and help him finally move on from the death of his mother.

At first Barry wanted to leave. He believed the speedforce was keeping him there. But when Cisco vibed in and called out to him, Barry decided to stay. He wanted to accomplish the speedforce's challenge of catching the shadow so that his powers would be restored. While Barry was chasing the shadow, the speedforce asked him if he knew that he was given speed for a very specific reason. This was reminiscent of what Oliver (Stephen Amell) said to Barry on the roof during the pilot, "That bolt of lightning chose you for a reason." The speedforce gave Barry his powers the night the accelerator blew up and it wanted him to understand why. It also wanted him to finally let go of his mother. The personification of Henry Allen took Barry to the cemetery where Nora was buried. Apparently Barry had never visited her grave. According to Barry he never came because he didn't want it to be real. In a beautifully touching scene Barry and Nora read to each other out of a book from his childhood, "The Runaway Dinosaur." Through this moment Barry was able to finally say goodbye to Nora. This allowed him to forgive himself for letting her die when he went back in last year's finale. When he forgave himself he caught up to the shadow -- it was him, his speed -- and he had it back. This whole sequence of events was a powerful emotional and psychological integration, where Barry could fully accept himself and his circumstances, and allow himself to feel worthy of the speedforce again.

The episode concluded with all of Team Flash cornered in S.T.A.R. Labs as Girder attempted to break down the door. Cisco tried to vibe one more time to bring Barry back, and Iris joined him, trusting that Barry would come home at the sound of her voice. He did return, and with his speed. He then took down Girder, which hopefully laid to rest any fear of future metahuman zombie outbreaks. Barry was able to miraculously wake up Jesse, and his dad decided to stay in Central City. Iris and Barry also got to share a WestAllen moment, as Barry told her that he was wrong to always look at what he had lost, when he had her right in front of him. "Your voice will always call me home." He was even able to visit his mom's grave. With Barry's speed back and his emotional confidence back stronger than ever, he is now ready to take on Zoom. What he doesn't know is that on Earth-2, Zoom is rallying a troop of dangerous metahumans who are determined to serve Zoom, overthrow Central City, and defeat The Flash. This episode perfectly set up the next two episodes of "The Flash," which will conclude season two.

Next week on "The Flash," Zoom brings his metahuman friends to Earth-1, including the doppleganger of a familiar face from "Arrow."

THE FLASH "Invincible" - (8:00-9:00 p.m. ET) KATIE CASSIDY GUEST STARS AS BLACK SIREN - After Zoom (guest star Teddy Sears) unleashes an army of Earth-2 meta-humans on Central City, Barry (Grant Gustin) is shaken when he sees their leader is the Black Canary's Earth-2 doppelganger, the Black Siren (guest star Katie Cassidy). Meanwhile, Wally (Keiynan Lonsdale) takes to the streets to help The Flash stop the meta-humans, which worries Joe (Jesse L. Martin). Iris (Candice Patton) and Henry (guest star John Wesley Shipp) are concerned about Barry taking on Zoom. Jesse Warn directed the episode with story by Greg Berlanti & Andrew Kreisberg and teleplay by Brooke Roberts & David Kob (#222). Original airdate 5/17/2016.

"Invincible" airs Tuesday May 17 on The CW at 8 p.m.