Ronnie Raymond and Martin Stein are separated. Everyone heads back to STAR Labs immediately, and before General Eiling's team hits the ground. He recognizes Firestorm separated immediately.

The two men, now separated, argue and spat like schoolchildren before Martin wants to go home and see his wife.

Surprisingly, Joe wastes no time showing Barry what he found at his old house. Barry hasn't been in the house since the night his mother was murdered. Joe turns on the "mirror" and Barry sees the 3D images. He takes no time getting to the point. The second speedster trying to stop the man in yellow was Barry. The look on Barry's face was full of emotion.

Joe, Harrison, Cisco and Barry chat about time travel by using Terminator and Back to the Future as their examples. 

Mason thinks it's cute that Iris thinks so highly of Harrison Wells that she doesn't immediately think to investigate.

It's handy to have Dr. Stein back since he knows about STAR Labs. Barry gets to the house to find he's jonesing for some Pizza. Some of Ronnie rubbed off on him.

Martin's really excited to talk about time travel. I mean, really excited. Barry, however, is sad that his destiny is to fail in saving his mother.

Caitlin shares with Ronnie about all the fun times she's had lately and he seems put off by it. He wants to take her away and start fresh. Her life is here. Ronnie, however, is about done with STAR Labs, especially since the particle accelerator took a year of their lives. 

When the place where Caitlin and Ronnie are hanging is attacked, Martin is affected. He feels panicked and knows The Flash has to go help Ronald. Eiling had a device made to attack Flash... micro-fragments attracted to kinetic energy.

Caitlin discovers all of Ronnie's and Martin's brainwaves are in sync. Totally impossible. Barry takes Ronnie home to stay and Iris happens to be making dinner for the night. Barry wonders how Joe got the blood sample tested exactly so and Joe admits they matched for everyone working at STAR Labs. Barry wants Joe to realize Harrison had nothing to do with his mother's death. He reluctantly agrees.

Meanwhile, Harrison and Martin are chatting. Martin wishes he had spent his life's work being the best husband he could be. Harrison drugged Martin and turned him over to Eiling.

Mason checks in with Iris about the shoot-em-up at the coffee shop. Iris digs a little deeper. She discovers Ronnie isn't her cousin, Sam. 

Martin is being kept at a remote location. Ronnie wants to go help him, wondering what happens to him if Martin's killed. She thinks close proximity will cause them to merge again, but he's willing to take that chance.

Harrison informs Ronnie that if they merge again, he doesn't know if they can be separated again. Ronnie knows there is a gun being held to Martin's head and Barry flashes into the facility and whisks Martin out.

Barry is covered in a chemical he has to run to burn off.

Harrison tells the two men to willingly merge to achieve a balance and when merged, they are able to work together. They hold him Eiling off for a minute and then Eiling tosses a weird ball in the air, full of ions. Barry flushes Eiling away and then he and Firestorm fly home.

The two men can now merge and separate at will, but it's unlikely they'll have any real sort of life. Ronnie and Martin are intending to head down the street from me, to Pittsburgh to visit with a colleague. 

Iris is excited to expose all of her friends and their work at STAR Labs. Or something.

Barry meets Joe at his old house again. He plans on saving his mother when he comes back to the house 15 years ago in the future. 

Harrison admits to General Eiling he is a metahuman and he looks out for his own. He invites Grodd in to take Eiling out.