Doctor Who: The Eleventh Doctor: Vortex Butterflies Part 3

The Doctor is on the trail of a being he cannot yet understand – something that looks strangely familiar to him… but without his companions to guide him, could he become lost to its mystery? Meanwhile, in London, Gabby and Cindy have been taken under the wing of ex-companion Sarah Jane Smith! Could she be the key in solving Gabby's unusual powers problems?