<Tr> <Th> 21 </Th> <Td> 21 </Td> <Td> "Grodd Lives" </Td> <Td> Dermott Downs </Td> <Td> Grainne Godfree & Kai Yu Wu </Td> <Td> May 5, 2015 (2015 - 05 - 05) </Td> <Td> 3J5371 </Td> <Td> 3.62 </Td> </Tr> <Tr> <Td_colspan="8"> While looking for Eddie and Eobard, Barry heads to stop a robbery at the gold reserve . When Barry confronts the would - be thief, they are both disoriented by an unknown psychological attack . Back at S.T.A.R. Labs, Iris confronts Barry about being the Flash . He is able to stop the thief, who turns out to be Eiling, whose mind is revealed to be controlled by Grodd . With a lead from Iris, Barry, Joe and Cisco head into the sewers to look for Grodd . The trio realize that Grodd is getting smarter and larger, and during an attack, Joe is kidnapped by Grodd . Cisco and Caitlin build Barry a device that will prevent Grodd's effect . It works, but the device gets damaged in a fight . Barry is able to fight off Grodd's psychic attack and trick him into jumping in front of an on - coming train . Eiling is freed . Iris reveals her feelings for Barry, but states her choice to be with Eddie . Grodd is revealed to be safe and roaming the streets . Meanwhile, Thawne works on a device that will allow him to return to his own time . He reveals to Eddie, Iris and Barry's marriage in the future . Later Thawne completes the device and is revealed to be hiding in a secret chamber inside S.T.A.R. Labs . </Td> </Tr> <Tr> <Th> 22 </Th> <Td> 22 </Td> <Td> "Rogue Air" </Td> <Td> Doug Aarniokoski </Td> <Td> Aaron Helbing & Todd Helbing </Td> <Td> May 12, 2015 (2015 - 05 - 12) </Td> <Td> 3J5372 </Td> <Td> 3.65 </Td> </Tr> <Tr> <Td_colspan="8"> Cisco discovers that Eobard has been supercharging his speed through his wheelchair, which is why he is so much faster than Barry . The particle accelerator is activated by Eobard, who has managed to repair it . The team is able to find and rescue Eddie, who ends his relationship with Iris . Worried that the metahumans imprisoned inside the particle accelerator will be killed when it reaches full power, the team plans to relocate them to Oliver's prison on Lian Yu . In order to set up a safe transport, Barry requests Leonard's help . Leonard agrees but only after Barry erases all of Leonard's criminal record . Leonard and Lisa sabotage the transport and allow the metahumans to escape, killing Simmons however . Eobard arrives back at the lab just as the accelerator fully charges . Barry, Firestorm and Oliver all meet outside to fight Reverse - Flash . They coordinate their efforts; Oliver stops him with a nanite injection that disables Eobard's speed and knocks him out . Oliver leaves after informing Barry of an upcoming help request . </Td> </Tr>

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