Shadow of the Tomb Raider is "climatic finale of Lara Croft's origin story"

UPDATE 15/3/18 1.00pm: And finally, Square Enix has made it official. As was leaked yesterday, Shadow of the Tomb Raider will launch on 14th September for PC, PlayStation 4 and Xbox One.

Here's a better version of the teaser being shown in cinemas:

Experience Lara Croft’s defining moment as she becomes the Tomb Raider. Shadow of the Tomb Raider will be revealed April 27th. Available on Xbox One, PlayStation 4, and PC on September 14th, 2018. pic.twitter.com/jujMf47kJH

— Tomb Raider (@tombraider) March 15, 2018

UPDATE 15/3/18 10.30am: Square Enix has still not officially comfirmed Shadow of the Tomb Raider, but its teaser trailer has now leaked online.

It looks like the gameplay footage is being shown in cinemas, attached to the new Tomb Raider movie. The trailer confirms the 14th September release date which leaked yesterday.

Here's a version of the trailer naughtily filmed off-screen from a cinema in France:

ORIGINAL STORY 14/3/18 1.50pm: Lara Croft's origin story will be brought to a close in the upcoming Shadow of the Tomb Raider, according to publisher Square Enix's website.

There's a teaser on the site for the game's upcoming announcement, due tomorrow - but in the site's HTML code the details can be seen already:

"Shadow of The Tomb Raider is the climatic finale of Lara's origin story. Available September 14th 2018."

Platform details mention PC, PlayStation 4 and Xbox One - with no mention of any exclusivity.

Shadow of the Tomb Raider is the unannounced but widely-expected next Lara Croft game. From the above description, it sounds like the final chapter in this iteration of the franchise.

We've known the game has been in development at Eidos Montreal - not Crystal Dynamics, which made 2013's Tomb Raider reboot and 2015 follow-up Rise of the Tomb Raider - for a while. Remember that leaked Shadow of the Tomb Raider presentation seen on the Montreal subway, back in November 2016?

Still, it feels an odd moment to call time on Tomb Raider's reboot subseries - just as the Alicia Vikander-starring Tomb Raider film hits cinemas. Perhaps there's no expectation of a movie sequel.

In a Eurogamer report published last January, I wrote about Crystal Dynamics and Square Enix Montreal's upcoming release schedule. Crystal is currently developing its announced Avengers project, while Eidos Montreal finishes Shadow of the Tomb Raider and begins production of Square Enix's second Marvel game - which we heard at the time would centre on the Guardians of the Galaxy team.

So, what next for Tomb Raider, with this younger iteration of Lara Croft seemingly on the out? It feels likely that Crystal will once again shepherd the series into yet another new era. Just recently, Tomb Raider writer Rhianna Pratchett discussed the possibility of an older, more grizzled version of the character.