Peter Harness has revealed that fans can look forward to a big cliffhanger during his upcoming Doctor Who two-parter.

It’s been confirmed that the Kill the Moon writer has put pen to paper for a double adventure which will be broadcast as Episodes 7 and 8 of Series 9. The episodes will mark the return of Osgood and the Zygons which Peter admitted is “a privilege”, albeit one that is ”a bit unbelievable”. “I think it’s quite an exciting story,” he told Digital Spy. “Unfortunately, I’ve got two fan favourites in my hands now, which can only set me up to disappoint people!”

He continued: “But it’s nice to do a cliffhanger, and I tried to write the biggest one I could.”

Filming for Series 9 is currently underway. It’s scheduled to air on BBC One in the autumn.