TV URBAN LEGEND: "Star Trek: The Next Generation" planned on killing off Commander Will Riker and replacing him with Lieutenant Will Riker.
One of the most fascinating things about science fiction is that it gives television shows a great deal of freedom with the casting of the shows, as there is always a fantastical reason why a character is now dramatically different that, say, "Cheers" would never be able to pull off. Heck, the notion of the same character being played by drastically different actors is at the very heart of the classic science fiction program, "Doctor Who."
"Star Trek: The Next Generation" was no stranger to this approach, as well, using the holodeck environment to let their actors take on completely atypical roles for their characters. Plus, of course, stuff like Patrick Stewart playing Locutus, the Borg-assimilated version of Jean-Luc Picard, or Denise Crosby playing Sela, the daughter of her earlier "Next Generation" character, Tasha Yar.
One of these little bits of fun acting opportunities came for Jonathan Frakes' Commander Will Riker in Season 6's "Second Chances," where the Enterprise heads to a science outpost to retrieve some data stored there that had beem left behind for eight years now. Riker had been on that outpost eight years earlier when he had barely escaped. His heroism had resulted in his quick rise in the ranks from Lieutenant to Lieutenant-Commander. As it turned out, though, when they got to the outpost, that when Riker had been beamed out eight years earlier, a freak accident had resulted in an identical copy of Riker being made. One of the Rikers was beamed off of the outpost while the other was sent back to the outpost, stranded for eight years. And now they were face to face!
Deanna Troi, Riker's former girlfriend, found a new interest in this version of Riker, as this was a Riker who never broke up with her to pursue his career.
In the end, the other version of Riker stuck around in Starfleet and also ended up breaking Troi's heart by leaving to take another assignment. He chose to take on his middle name, Tom, as his new first name. Tom Riker would pop up from time to time on various "Star Trek" shows.
However, the writers for "Next Generation" originally considered a much more drastic ending to the episode. You see, one of the recurring problems from a story perspective on the series was that it made no sense for the first officer of the prized ship in Starfleet to go on so many heroic mission and have so much success and not actually become the captain of his own ship. It was stretching the point to incredulity that Will Riker would not accept a ship of his own where he would be the Captain.
So, according to the commentary tracks on the third season of "Star Trek: The Next Generation" on Blu-Ray, the writers initially considered killing off Commander Riker and then having Lieutenant Riker (whether he would call himself Will or not is up for debate) join the crew, with Commander Data becoming the new first officer for the ship and Riker taking Data's old job as the head of operations. It would explain why Riker wouldn't leave the ship, as he would now be at a very different point in his career. It would also create all sorts of new dynamics, with Data as first officer and with the other Will re-meeting all of the crew of the ship and presumably he would pursue a relationship with Troi again.
However, the main issue was this was late in the show's run, and they had been discussing a film version of the show for some time now, and it just seemed like a bad time to drastically alter the framework of the show, so the idea was scrapped.
A few years later, then-"Next Generation" writer Ronald Moore made the same proposal for an episode of "Star Trek: Deep Space Nine" where Colm Meaney's Miles O'Brien was replaced by a sleeper agent replicant. That idea was also denied.
The legend is...
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