I haven't yet seen this week's Doctor Who episode, "The Time of Angels," but I have seen the promo for the following episode, "Flesh and Stone." Like "The Time of Angels," "Flesh and Stone" will focus on the Doctor's fight against the Weeping Angels, deadly statues that can only move when you're not looking. Blink, and you're dead.
It also looks like we'll get some expansion on the crack motif that has been appearing throughout the Doctor's travels this season. Maybe we'll get a little light into what these cracks are.
"Flesh and Stone" is the second part of a two-part story, with the first being "The Time of Angels." It will premiere in the UK on BBC One on May 1, and in the US on BBC America on May 15.