J.J. Abrams' reboot of the Star Trek franchise was crafted in a way to both bring fans back to the era of the original USS Enterprise and its crew led by Captain James T. Kirk while also taking place in the same continuity. Sort of. And it took advantage of its time-travel plot device to ensure its authenticity by bringing back one important familiar face in Leonard Nimoy's original Vulcan Science Officer, Spock.
Nimoy had a brief cameo in the sequel, 2013's Star Trek Into Darkness, as well and over the course of the development of all these films the question was raised on whether or not the original Kirk played by William Shatner could be worked into one of these films. Shatner had a scene in the original 2009 Star Trek scene that was cut for fear of it being just a "gimmick" and in 2014, it was reportedly part of the script for the three-quel Star Trek Beyond. It's not anymore though.
About a year after Star Trek Into Darkness opened in theaters, and many months after J.J. Abrams traded the captain's chair of Star Trek 3 to join Lucasfilm and Disney to direct Star Wars: Episode VII, Trek co-writer and producer Roberto "Bob" Orci was set to takeover the director's chair. It was Orci's script for Star Trek 3 that had reportedly included a scene reuniting Nimoy and Shatner. At the time, Shatner said he hadn't been contacted but wouldn't deny rumors either.
Of course, at the end of 2014, all of that was thrown out by Paramount Pictures. Something happened and Orci was out of the director's chair, replaced by Justin Lin. His script tossed out. He has a producer credit but that would reportedly be in name only. The passing of Nimoy a year ago in addition to all the changes behind the scenes during early development of Star Trek Beyond eradicated any chance of seeing Shatner play Kirk once again for the first time since 1994's Star Trek: Generations.
In an interview with SFX Magazine, Shatner states that "there as never a conversation" about him returning for the 50th anniversary of Star Trek, at least not a "substantial" one.
“It would have been interesting to see what their fertile imaginations could have done with somebody who is 20 years older than when Captain Kirk died [in Star Trek Generations] and how they would have explained the difference in appearance. But that never came up. I’m sure they must have thought of it one time or another but I never had a substantial conversation about replaying the role.”
For Trekkies looking for more OG Kirk though, Shatner is hosting the first ever official Star Trek cruise - an adventure coming in 2017 that sold out in less than two months. And as for the franchise, Star Trek Beyond isn't all that's on the way. Stars Chris Pine and Zachary Quinto both signed for Star Trek 4, ensuring the future of the film franchise, while CBS develops a new Star Trek TV show that'll air on its digital streaming service.
Bringing old school Kirk - who died in the original timeline but could be alive while older in the reset continuity - would be a neat nod for fans but given what we know about Star Trek Beyond and saw in its awkward first trailer, such a plot point just doesn't fit and would be just a gimmick. Still, with the 50th anniversary and Shatner interested, it seems a wasted opportunity for Paramount and CBS not to do something with Shatner or the other Captains.