Doctor Who spin-off The War Between the Land and the Sea looks to he heading for an autumn transmission date, with the launch of a UNIT Headquarters website designed to build anticipation for the new series.

Visitors to the UNIT site, which can be accessed with a BBC online account, can read messages from the likes of Kate Lethbridge-Stewart and Osgood, as well as browse the Black Archive, an inventory of top secret artefacts.

Osgood reports she’s been ‘painstakingly recording and logging these items’, one of which is a Homo Aqua egg recovered from Dragonera Island, Earth, and previously glimpsed in the trailer screened at the conclusion of the last series of Doctor Who.

Cultbox speculates that Homo Aqua could be a term for the Sea Devils, the classic era monsters first encountered by Jon Pertwee’s Doctor which have long been rumoured to be making a comeback in the forthcoming drama. Their involvement is as yet unconfirmed, with the creatures shown in the trailer not bearing a resemblance to any version of the Sea Devils in their previous appearances. A redesign is a distinct possibility, of course, as with the Silurians (or ‘Homo Reptilia’) when they were resurrected for the new series in The Hungry Earth/ Cold Blood in 2010.

The five-part series is written by Russell T Davies and Pete McTighe and directed by Dylan Holmes Williams. It will star Russell Tovey as Barclay and Gugu Mbatha-Raw as Salt, and also feature familiar Doctor Who faces Jemma Redgrave as Kate Stewart, Ruth Madeley as Shirley Anne Bingham, and Alexander Devrient as Colonel Christofer Ibrahim.

The War Between the Land and the Sea will air on BBC1 in the UK, and exclusively on Disney+ in other territories. Unless the BBC’s Doctor Who co-production deal with Disney is extended, it will be the last set of episodes to air under that arrangement.