The screening was followed by an Q&A with its stars John Barrowman, Eve Myles, and Bill Pullman, and writer/executive producer Russell T Davies; other members of the cast and crew were present in the audience, including Kai Owen, Tom Price, executive producer Julie Gardner and director of episode one, Bharat Nalluri.
Avoiding spoilers for what comes up later in the series, the guests focused upon their many anecdotes from the shoot, with Barrowman and Myles discussing the excitement of making the show at Warner Bros - not to mention the pranks the former likes to pull! - and Pullman commenting on what it was like to work with his Welsh co-stars on the project. When asked about if the show could become fully "American" in later (potential!) series, Davies indicated that he'd want Torchwood to remain Welsh at its heart.
Highlights from the Q&A are expected to be available to watch on the BFI website from next week.
Prior to the screening, the press were able to chat to the stars about the show, and the BBC have published an article including a video interview featuring Barrowman, Myles, Pullman and Davies discussing their thoughts on making a new, co-funded series in America.
Bill Pullman appeared on BBC's Breakfast this morning, discussing the development (and name!) of his character, and also on what he thought of Russell T Davies:
I wasn't expecting - I'm thinking prototypical Welsh like Anthony Hopkins or Richard Burton, dark, moody - but he's bright, just such a passion, he is such a generous spirit, and very special to everybody that works with him. He has really, now, quite a following in the States - he and Julie Gardner run a very professional operation.
Davies himself can be heard discussing how he took the show from Wales to Los Angeles tonight on Front Row (BBC Radio 4) from 7:15pm.