Dr who - series 6 - The Sound of Dolls/Clones/Silence?

Two young actresses,Fern Deacon and Frances Encell are now listed as appearing in Doctor Who. Frances Encell's CV says she is performing a Voice over, and after a quick search I discovered Fern Deacon's fan site which confirms she's also doing voice over work.

Could these young actresses be appearing in Episode Seven, which has just begun filming?

Since they are both with the same acting agency it’s also possible that they’re appearing in an earlier episode and their CV’s have only just been updated.

Might they be providing the voices for the clones in Matthew Graham’s two-parter, The Rebel Flesh and Gangers? Could they be giving a voice to the creepy dolls in Mark Gatiss’ episode What Are Little Boys Made Of? Or even more tantalising perhaps they’re giving voice to the Silents in Moffat’s opening two-parter.

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