Good question … why didn't NBC cast the new "Ironside" with an actor who actually uses a wheelchair?
The most likely answer is a combination of two factors: 1) Blair Underwood was already under contract to star in a series to be specified, and 2) NBC feels they need a recognizable "star" to promote the re-imagining of a famous, but maybe only second-tier famous, series of the past. These are good reasons.
On the other hand, my sense is that new TV series with big name stars don't necessarily do better than series anchored by relatively unknown actors. In fact, it seems more like a sign of lack of confidence in the series itself … as if it can't stand on its own quality and needs a star to make it viable. And the fact remains that there are good actors out there who have disabilities, who could bring an extra dose of authenticity to a role like Chief Ironside, in which the main feature that distinguishes him from your run-of-the-mill police procedural sleuth is the disability. I like that that the new Ironside will be African-American, but it might have been even more interesting to cast a woman with a disability in the role, (a la Starbuck in the new "Battlestar Galactica", as long as they are focusing on the actor over the script.
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