"Legends of Tomorrow" has tapped Matthew MacCaull to guest star in Season 2. MacCaull, whose known for his role on "iZombie" and "Bates Motel," will take on the role of Henry Heywood Sr. aka DC comics character Commander Steel.

According to Entertainment Weekly, not much details have been spilled about how Commander Steel will figure into "Legends of Tomorrow" Season 2; however, the publication noted that Commander Steel is in fact the grandfather of Dr. Nate Heywood, aka Citizen Steel. Nick Zano has been tapped to play the latter.

The casting comes after the producers' retooling of "Legends of Tomorrow" Season 2, which has been previewed to introduce the Justice Society of America (JSA). Part of this storyline also includes the arrival of Rex Tyler aka Hourmans (Patrick J. Adams) who was the first to appear on the show. Subsequently, other JSA members such as Obsidian, Stargirl and Mid-Nite are also expected to make an appearance as the new season progresses. No word yet on who will play the trio.

"Legends of Tomorrow" Season 2 will also see the arrival of new villains dubbed as "The Legion of Doom," Variety has learned. This new group of Big Bad will consist of familiar faces from "Arrow" and "The Flash," specifically Malcolm Merlyn (John Barrowman), Damien Darhk (Neal McDonough), the Reverse-Flash (Matt Letscher) and Captain Old (Wentworth Miller).

As revealed earlier this month at Comic Con, "Legends of Tomorrow" Season 2 will also feature a guest appearance of "Arrow" lead star Stephen Amell. Other highlights from the panel include the return of Jonah Hex in episode 6 and a potential new love interest for Sara.

"Legends of Tomorrow" Season 2 premieres on Thursday, Oct. 13 at 8PM on the CW.