Ripper Street will air extended episodes exclusively on Amazon Prime Instant Video when it returns for a third series.
The period thriller's latest 8-part run is a co-production between the BBC and Amazon.
Prime customers will be able to watch the new extended episodes from late 2014, with the show being cut down to fit an hour-slot when it airs on BBC One in 2015.
"We don't have a 60-minute slot to fill at 9pm," explained Chris Bird - Amazon Instant Video Film & TV Strategy Director.
"So we said to Richard [Warlow, series creator], 'We want you to write this season completely unencumbered. If you want to write a 70-minute episode, write a 70-minute episode'.
"I think that's one of the areas of flexibility that we do offer content makers - there are no rules for us in terms of what we can and can't do."
What to Read Next
Amazon is yet to decide if it will release the third series of Ripper Street in one batch or in instalments.
Ripper Street returns: Fan outcry at axing led to revival, say stars
Watch a trailer for Ripper Street below:
