In the seventh episode of Doctor Who‘s new series, Amy Pond has been kidnapped and the Doctor is raising an army to rescue her. But as he and Rory race across galaxies, calling in long-held debts and solemnly given promises, his enemies are laying a carefully concealed trap.

In her cell in Stormcage, River Song sadly acknowledges that the time has come at last – today will mark the Battle of Demons Run and the Doctor’s darkest hour. Both sides will make their sacrifices and River Song must finally reveal her most closely guarded secret to the Doctor.

> Order the Series 6 Part 1 DVD on Amazon.

> Order the Series 6 Part 1 Blu-ray on Amazon.

‘A Good Man Goes To War’ airs on BBC One at 6.40pm on Saturday 4th June. In the meantime, here are some teasing hints for the episode…

» The Sontarans, Judoon, Silurians and Cybermen are all back.

» Simon Fisher-Becker returns as big blue Dorium Maldavar, last seen with River Song in ‘The Pandorica Opens’.

» Dorium “becomes a bit of a hero”, according to actor Simon Fisher-Becker, who also reveals that “a lot of questions will be answered, but then a whole bucket load of new questions will come forward”.

» Rory’s Roman costume returns.

» Karen Gillan has told Radio Times that “we discover who River Song really is” and “it’s such a huge pay-off, I didn’t see it coming”.

» Colonel Manton is “a powerful leader, a scary man and a fearsome soldier” who is “obsessed with killing the Doctor”, according to actor Danny Sapani.

» Frances Barber has told Total TV Guide that ‘eye patch lady’ Madame Kovarian is “involved in Amy’s pregnancy – before and after the birth – and is in charge of a band of soldiers”.

» The Sunday Times reveals that Amy’s baby is named Melody.

» There’s “a sort of Nazi state”, according to guest star Charlie Baker, who also describes the story as “one of the darkest episodes ever”.

» Catrin Stewart plays a character named Jenny. It’s unknown if this is a regenerated incarnation of the ‘Doctor’s daughter’ from Series 4, but – with a major character named Jen in the previous two-part story – it seems an unusual name choice if it’s not her.

» The episode is “more disturbing than scary”, according to Karen Gillan.

» Director Peter Hoar has summarised the episode as “a bit of a rollercoaster ride through all different times, space, everything”.

» Hugh Bonneville is rumoured to return as ‘The Curse Of The Black Spot’‘s Henry Avery, alongside Oscar Lloyd as Avery’s son Toby.

» Part of the story is set in Jack the Ripper era London.

> Follow us on Twitter to get the latest Doctor Who teasers and reviews first.