With two key roles already secured, Fox is continuing to round out its cast for the reboot 24: Legacy. Deadline reports that Ashley Thomas has signed on for a third lead role in the new series, which will be a complete reboot that doesn't feature the iconic 24 character Jack Bauer, played by Kiefer Sutherland. Ashley Thomas is playing Isaac Carter, the older brother of the series' main lead, Aaron Carter, played by Corey Antonio Hawkins.

This report reveals that Isaac and Aaron are not on good terms, with a bitter past that includes Aaron marrying Isaac's former girlfriend Nicole (Anna Diop). It was previously reported that Aaron grew up in a rough neighborhood and had a troubled childhood, which he managed to escape by joining the Army Rangers. When the series begins, Eric is back home in Virginia with his wife Nicole, who has yet to be cast, when he is pulled back into action as his past catches up with him. Our report from earlier this month revealed that he asks the CTU for help in saving his life, and stopping what potentially could be one of the largest-scale terror attacks on American soil.

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The cast also includes Miranda Otto as the female lead, Rebecca Ingram, the former head of the CTU who is said to be having second thoughts about leaving the counter-terrorist unit. She is now married to Senator John Donovan, who will be played by Jimmy Smits. The cast also includes Teddy Sears and Dan Bucatinsky, but no details have been given for their charactrs.

The show will retain the real-time, pulse-pounding, fast-paced format with split screens and complex interweaving storylines, with each episode representing one hour of an eventful day. Howard Gordon (Homeland, 24), Manny Coto (24) and Evan Katz (24) will serve as executive producers. The project will be produced by 20th Century Fox Television, Imagine Television and Gordon's Teakwood Lane Productions. Production on the pilot is said to begin sometime this winter, but a start date has not yet been revealed.

Ashley Thomas can currently be seen on the UK miniseries Beowulf: Return To The Shieldlands, and he previously had a recurring role on Criminal Justice. On the big screen, he starred in Cockneys Vs. Zombies, The Man Inside and My Brother the Devil. It isn't known how many other roles 24: Legacy needs to fill out, so stay tuned for more casting updates for this upcoming reboot series.