01/04/2013 19:11 BST | Updated 01/06/2013 06:12 BST

PICTURE: Matt Smith And David Tennant At 50th Anniversary 'Doctor Who' Read-through

A sleuth of bears... a murder of crows... what do you call a collection of Time Lords?

Stephen Moffat may have to invent a word in time for the 50th anniversary of 'Doctor Who' because, as this first picture shows us, preparations have begun.

David Tennant and Matt Smith were snapped at a read-through for the special edition, filming for which begins this week.

And we'll be keeping our eyes peeled for more distinctive characters lurking around the studio. Billie Piper is already confirmed to be joining the party, for what is gearing up to be one of the most highly-anticipated TV shows ever.

Meanwhile the current series of 'Doctor Who' continues this Saturday 6 April at 6:15pm with 'The Rings of Akhaten', with the eleventh Doctor* now ably abetted by new assistant Clara, played by Jenna-Louise Coleman.

MORE: 'Doctor Who' Review - He's Back, And In Reassuringly Fine Form...

*This article originally said 'tenth' which was spotted by eagle-eyed fans. So I've bowed to public pressure and included the Time Lord I wasn't sure should be included...