Arrow Season 3 Spoilers: 'The Atom' Gets His Name in New Clip from 'The Flash'

Brandon Routh debuted as Ray Palmer on Season 3 of the CW's Arrow, but it appears he finally gets his moniker of "The Atom" over on The Flash.

Ray and Felicity (Emily Bett Rickards) visit Central City in a new episode of the series, and the following clip shows how the Atom gets his name:

In case you missed it, the official description for Episode 21, entitled "Al Sah-Him," has now been released.

The description reveals that the League of Assassins has an intriguing new target. Check it out below:

"ARROW

'Ah Sah-Him' — (8:00-9:00 p.m. ET) (Content Rating TBD) (HDTV)

THE LEAGUE OF ASSASSINS SETS THEIR SITES ON NYSSA — Oliver (Stephen Amell) goes through a rigorous transformation. The League of Assassins sets their sites on Nyssa (guest star Katrina Law), who is back in Starling City training Laurel (Katie Cassidy). When Nyssa realizes they are coming, she arms up to face them alone but Laurel asks Felicity (Emily Bett Rickards) and Diggle (David Ramsey) to help protect her new friend. Thor Freudenthal directed the episode with story by Beth Schwartz and teleplay by Brian Ford Sullivan & Emilio Ortega Aldrich (#321). Original airdate 4/29/2015."

In other news, filming on the Season 3 finale has begun, and executive producer Marc Guggenheim has revealed the title of the episode on his Twitter page.

The showrunner revealed that the episode is entitled "My Name is Oliver Queen," which any Arrow fan would recognize as the first line of Ollie's opening monologue in each episode.

Arrow's third season finale begins production today. pic.twitter.com/sHJABr1253

— Marc Guggenheim (@mguggenheim) April 8, 2015

What do you think of the clip? Let us know in the comments section.