Doctor Who: 10 Things You Didn't Know About The Twelfth Doctor
We do know he's a good man, but what DON'T we know about the Twelfth Doctor?

Unlike his predecessors, the Twelfth Doctor wasn't a hugger or a cryer, meaning that he often wasn't very forthcoming with his feelings. Look at how he lied to Clara about finding Gallifrey again at the end of Death in Heaven, for example. And yet, as Steven Moffat once observed, the Twelfth Doctor is a raw nerve of emotion, depicting his centuries of adventuring, love and loss with just a look.
So what do we know about the Twelfth Doctor and actor Peter Capaldi? We know that, like Colin Baker before him, Peter Capaldi had played another role in the show prior to being cast as the Doctor. We also know that he was briefly considered for the Eighth Doctor, but turned down an audition for the 1996 TV Movie.
However, there are also other little elements of the character that have only really been explained outside the show. Elements like the ring he wears throughout his three seasons, or the reasons behind the increasing height of his hairstyle. We've dug deep into the archives to bring you these and more things you never knew about the Twelfth Doctor...
10. He's Wearing Peter Capaldi's Wedding Ring

Throughout his era, the Twelfth Doctor wears a band on his ring finger. There's no story reason given for this item of jewellry, though Paul Cornell's novelisation of Twice Upon A Time stated that it's his wedding ring from his marriage to River Song.
However, the real reason that the Twelfth Doctor wears a ring, is because it's Peter Capaldi's actual wedding ring from his marriage to actor and producer Elaine Collins. Albeit with a sci-fi upgrade.
Capaldi didn't want to take off his wedding ring for the role, and so asked if he could incorporate it into the Twelfth Doctor's costume. The idea was that a second ring would be made, with a disc joining Capaldi's wedding ring with the new piece of jewellry.
This second ring - the one with the green stone - was made by Rowley's jewellers in Penarth. Touchingly the son of one of the jewellry makers conceived of the origins for the Doctor's ring.
“This timeless gold ring contains green amber collected by the Doctor on the planet Raxacoricofallapatorius. It reminds him of all the wars he has won but also all the lives he has taken. This thought lurks on his conscience to this day. To Peter, Best wishes being the New Doctor Who from Idris (11) “