The Flash -- "Potential Energy" -- Image FLA210a_0286b -- Pictured: Jesse L. Martin as Detective Joe West -- Photo: Jack Rowand/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210a_0363b -- Pictured (L-R): Jesse L. Martin as Detective Joe West and Keiynan Lonsdale as Wally West -- Photo: Jack Rowand/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210a_9517b -- Pictured: Keiynan Lonsdale as Wally West -- Photo: Jack Rowand/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210a_9530b -- Pictured: Keiynan Lonsdale as Wally West -- Photo: Jack Rowand/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210a_9546b -- Pictured: Jesse L. Martin as Detective Joe West -- Photo: Jack Rowand/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210a_9625b -- Pictured: Keiynan Lonsdale as Wally West -- Photo: Jack Rowand/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0004b -- Pictured (L-R): Danielle Panabaker as Caitlin Snow and Teddy Sears as Jay Garrick -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0035b -- Pictured: Grant Gustin as Barry Allen -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0069b -- Pictured: Shantel Van Santen as Detective Patty Spivot -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0078b -- Pictured (L-R): Shantel Van Santen as Detective Patty Spivot and Grant Gustin as Barry Allen -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0096b -- Pictured (L-R): Shantel Van Santen as Detective Patty Spivot and Grant Gustin as Barry Allen -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0107b -- Pictured: Shantel Van Santen as Detective Patty Spivot -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0129b -- Pictured (L-R): Danielle Panabaker as Caitlin Snow and Teddy Sears as Jay Garrick -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0134b -- Pictured: Grant Gustin as Barry Allen -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0205b -- Pictured: Grant Gustin as The Flash -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0251b -- Pictured: Grant Gustin as The Flash -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_BTS_0270b -- Pictured (L-R): Behind the scenes with Grant Gustin as Barry Allen and Shantel Van Santen as Detective Patty Spivot -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.

The Flash -- "Potential Energy" -- Image FLA210b_0287b -- Pictured: Grant Gustin as Barry Allen -- Photo: Katie Yu/The CW -- © 2016 The CW Network, LLC. All rights reserved.