The blue chip doc series generated excellent linear ratings and the opening episode was requested 3.8 million times alone, as the show took the overall number one iPlayer slot.
The UK pubcaster issued new iPlayer stats today and said 2016 has been a record year for the service, with 243 million monthly programme requests.
Peak months, ahead of an anticipated seasonal surge, were October and November.
Amid criticism that content on the BBC Three service was hard to find after it moved from linear to online only, the BBC claimed its youth-skewed net had a banner year on iPlayer.
The debut episode of BBC Three drama Thirteen was requested 3.2 million times, the second most popular episode of any series this year.
The BBC added that edgy comedy Fleabag fared well on iPlayer, with 6.7 million views across its series run.
The pubcaster also singled out spy drama The Night Manager, cooking competition Great British Bake Off, and the New Year Sherlock special The Abominable Bride as strong performers.
Sport programming was also popular in terms of live streaming, with the Olympics popular and the England vs Wales Euro 2016 game the most-watched live event of the year.
Charlotte Moore, director of BBC content, said: “From Bake Off, The Night Manager, Thirteen, Sherlock, Our Girl, Fleabag and even live football – it’s an exceptional service that we will be taking to the next level in 2017.
“This Christmas promises even more opportunities for viewers to watch their favourite shows from our incredible festive schedule.”