Jason O'Mara in Life on Mars by Vivian Zink/ABC Jason O'Mara in Life on Mars by Vivian Zink/ABC

There was a brief pause, but soon enough The Big Question led off the Life on Mars TCA press tour session: "Why all the retooling of the pilot?"

Josh Appelbaum, who with Andre Nemec and Scott Rosenberg succeeded David E. Kelley as executive producer, spoke first of the change-of-setting - from the City of Angels to the Big Apple. He said that while they are "huge fans" of the British Life on Mars - in which a police detective is mysteriously transported three decades into the past - they feel that an early-'70s cop drama is best married to New York City. Added Nemec, "Our goal was to honor the BBC series, and we're excited to bring the spirit of that show to 1973 New York."

ABC's Mars has undergone several cast changes since the pilot was shot, including the addition of Michael Imperioli and Jonathan Murphy as series lead Jason O'Mara's fellow cops. "I'm the only survivor - call it Irish luck," quipped O'Mara. "It can be a little weird [enduring such an upheaval]," he added. "I was really sad to see I wasn't going to be working with [the original ensemble], but at the same time I understood the decision. Those other actors are all now back working, so it worked out fine in the end."

Thus far, the key role of Gene Hunt (played by Philip Glenister for the BBC) has yet to be cast. Asked if Glenister himself is a possibility, the producers said no, explaining that, among other reasons, he's busy with the BBC's Mars spin-off.

Another deviation from the original series has to do with how O'Mara's detective ccomes to be transplanted into the '70s. Across the pond, viewers were offered two main possibilities that Sam Tyler was in a coma, or he had lost his mind. ABC's take will make things far murkier. "We asked the creator [of the BBC Mars] for permission to change the mythology," says Appelbaum. "Each week we'll be deepening the mystery about what's going on with Sam. We'll throw in many more options."

Those "more options" however won't fuel an endlessly looping, inevitably hard-to-resolve mystery. "We know exactly where this is all going. We do," promises Appelbaum. "We worked on Alias and know the pitfalls, so we know where this is going to end." - Matt Mitovich

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