Cahill will take on the role of Sam, a former EMT and brother-in-law to the notoriously difficult Big Jim (Dean Norris). The character will also form a "deep connection" with Rachelle LeFevre's Julia Shumway.
This should certainly shake things up, as Julia and Barbie (Mike Vogel) are still in the throes of their romance (in spite of Barbie having killed Julia's husband -- whoops!), and Barbie will probably be understandably not thrilled to see Julia form any kind of a "deep connection" with anyone else, let alone a relative of Big Jim's.
Then again, Season 1 ended with Barbie in quite the life-or-death situation (at Big Jim's hands, no less,) so hopefully he'll still be around to have strong feelings of any kind toward this Sam/Julia "connection."
The show has also added relative newcomer Karla Crome, a former series regular on the British science fiction dramedy 'Misfits.' For her first big stateside role, Crome will be playing Rebecca, a smart and tough school teacher who is also a former army brat.
One wonders where these new characters are going to come from, considering all the main characters are trapped in the town of Chester's Mill, under the titular dome. Big Jim has a never-before-seen handsome brother-in-law that shows up out of nowhere for Season 2? Where has he been hiding all this time?
The second season of 'Under the Dome' kicks off on June 30.