Yes, 1 (2013) is free to watch on Rakuten TV in the UK with no subscription required.

Where can I watch 1 in the UK?

1 (2013) is available to stream on Plex, Rakuten TV in the UK.

Is 1 on Rakuten TV UK?

Yes, 1 (2013) is currently available to stream on Rakuten TV UK.

Yes — it's on Rakuten TV

Available to stream now

Documentary

Is 1 free to watch?: Yes, 1 is free to watch on Rakuten TV in the UK with no subscription required.
Where can I watch 1 in the UK?: 1 is available to stream on Plex, Rakuten TV in the UK.
Is 1 on Rakuten TV UK?: Yes, 1 is currently available to stream on Rakuten TV UK.