Peter Capaldi dressed up as the Third Doctor and looked VERY happy about it

The Twelfth Doctor – who this Christmas handed over the keys to the Tardis to his replacement Jodie Whittaker – has been a devotee of the show since childhood with his adoration of all things Who well documented by the media and fans since he took over the role in 2013.

• Fans say Jodie Whittaker nailed her Doctor Who debut but Peter Capaldi ruled the Christmas special
• Doctor Who: everything we know about Jodie Whittaker’s new Doctor – UPDATED!
• Karen Gillan and Pearl Mackie have some advice for Jodie Whittaker’s new Doctor Who companions

So it comes as no surprise that Capaldi bowed out in style. Mark Gatiss – who has written a number of episodes for the BBC sci-fi series and starred as a WWI soldier in the Christmas special – posted a picture of the outgoing Doctor on Twitter after his final episode aired.

It shows Capaldi playing fancy dress on his last day on set, trying on Third Doctor Jon Pertwee's velvet jacket from Planet of the Daleks. And surprise surprise, the grin on his face is almost as big as the mop of hair on his head.

https://twitter.com/Markgatiss/status/946339442473750528

Take a closer look at the snap and you can also see Gatiss's reflection in the mirror, clearly enjoying the moment too.

Capaldi's regeneration drew praise from viewers on Christmas Day as 5.7 million tuned in, with many RadioTimes.com readers lauding the actor for his exit from the Tardis.

Doctor Who will return for a new series next year with Jodie Whittaker – the first female Doctor – at its helm, overseen by new showrunner Chris Chibnall.