Victor Garber, who starred as Jennifer Garner father on J.J. Abrams’ Alias TV series, is joining the cast of The Flash in a major recurring role as the DC Comics character Dr. Martin Stein, the nuclear physicist, who becomes half of the Firestorm character, when he is fused with the younger Ronnie Raymond, who will be played on The Flash by Arrow star Stephen Amell’s cousin Robbie Amell (see "Firestorm to Appear in 'The Flash'").
 
According to The Hollywood Reporter, Garber will join The Flash cast in episode 12 of the first season (the Firestorm saga may well dominate the final arc of the show’s first season).  Garber’s Dr. Stein is the latest announced DC Comics character set for the first season of The Flash, joining Dr. Tina McGee (played by Amanda Pays), General Wade Eiling (Clancy Brown), Heatwave (Dominic Purcell), and Captain Cold (played by Wentworth Miller--see "First Look at Wentworth Miller as Captain Cold").
 
The Flash debuted on Tuesday with an audience that numbered 4.8 million, the biggest debut on the CW since The Vampire Diaries in 2009 (see "'The Flash' Posts the Best CW Debut in Five Years").