Steven Moffat recorded a radio interview in which he reveals several facts about Jenna-Louise Coleman's character:

- The new companion will again be from contemporary Earth. This is necessary for audience identification and a ‘jumping on’ point for new viewers.

- How the companion gets where she is and what that means for the character is what will make her utterly different and fascinating.

- The new companion will not have any links to any previous characters.

- Her ‘journey’ will be shocking and intriguing. The Doctor has never met anyone quite like her before.

- Her very presence in the TARDIS will change the Doctor and there’s something different about her that will have a knock-on effect for the Doctor/companion dynamic.

More information is due to be released soon, so watch this space!