Mundy Flynn will be acknowledged. In the first full trailer for Doctor Whos next series (number 15 or season two, depending on how youre counting), we see Varada Sethus new companion Belinda Chandra looking puzzled at a picture of herself on the TARDIS scanner.Shes right to look puzzled, because the picture is of Mundy Flynn, the ordained Anglican marine character Sethu played in a series 14 episode. (And because Doctor Who loves an Easter Egg, when Belinda correctly identifies the TARDIS as a time machine later on in the trailer, the Doctor responds with Boom! the name of that very episode.)Theres something already connecting us, says the Doctor in voiceover as we see a clip of Flynn introducing herself. Evidently. And were about to find out what that is, starting from Saturday April 12, with new episodes available from 8am on BBC iPlayer followed by a BBC One broadcast that evening in the UK, and streaming from 12:00 am PST in the US and around the world on Disney+. Heres the first full trailer:With glimpses of multiple new episodes, locations, monsters, and guest stars plus the return of familiar faces from UNITs Kate Lethbridge Stewart and Mel Bush to Anita Dobsons Mrs Flood and Millie Gibsons Ruby Sunday, here are a few of the trailers major talking points.Belinda the Nurse ChandraJudging by the nondescript contemporary bedroom in which Belinda Chandra (Varada Sethu) wakes up in the first seconds of the trailer, the new companion is another human from roughly, now. What though, is behind the flashing lights that have roused her from her IKEA bed in the middle of the night?We see Belinda later fiddling with what looks like a saline drip and responding to the Doctors customary introduction that his name is Just the Doctor with the line, Alright then, Im called the Nurse. Is she another medical companion to follow in Martha Jones footsteps?She seems to be a reluctant companion, at least to begin with, telling the Doctor, I am not one of your adventures and demanding that he take her home, which he promises to do, albeit the long way around. But mysterious forces are stopping that from happeningNew MonstersWhile the Doctors voiceover reminds us of the recurring theme that there are forces beyond this universe and vast creatures looking down on us, we see UNIT boss Kate Lethbridge Stewart walking along what looks like a high-security UNIT corridor as a slimy monster contained in one of its cells slams against the viewing window. Shudder.At 0:16, a leggy skeleton dinosaur-ish creature towers above some rooftops, followed by a silhouetted spiny creature at 1:18 thats seen reaching a bony hand onto the shoulder of guest star Jonah Hauer King as Ruby Sunday explains, It wants you scared Because it likes the taste. At 1:34, theres a giant spider creature thats more robotic-looking than a Racnoss, but just as likely to haunt childrens nightmares.Add to that the already-revealed Mr Ring-a-Ding, a 1950s cartoon character who steps out of the screen and into the real world, plus, at 1:07, a ghostly mask that could well come from episode five, which is thought to guest-star Rose Ayling-Ellis and is being touted by showrunner Russell T Davies as the scariest episode theyve ever made.Join our mailing listGet the best of Den of Geek delivered right to your inbox!Space EurovisionIf theyve timed this just right, then the Eurovision-themed episode (rumoured to have been written by new screenwriter Juno Dawson), which guest-stars TV presenter Rylan Clark will air on the same day as the actual contest this year on Saturday May 17. In the trailer, Clark is seen standing alongside a feline co-host played by French actor Julie Dray, and welcoming a huge crowd to the Interstellar Song Contest, in the audience of which is a certain someoneMrs Flood ReturnsI love a good show, says Anita Dobsons mysterious recurring character Mrs Flood in the crowd of the Eurovision episode. Probably just a fun night out for the girl, nothing malevolent or Doctors granddaughter-ish or Masterly to see here (?).Speaking of returning formidable women, it looks as though Mel Bush (Bonnie Langford) has shaken off last series Sutekh possession and has dropped the ritualistic robes for a nice cardigan in her trailer appearance, in which she looks absolutely bloody terrified as the world around her crumbles and the Doctors voice is heard warning our entire reality is in danger. Not again!New Guest StarsAs well as Mr Ring-a-Ding, the cartoon character voiced by Alan Cumming, and Jonah Hauer King popping up opposite Millie Gibson, we also catch a glimpse of Australian Slow Horses actor Christopher Chung in uniform as Trooper Cassio Palin, while a man shouts Helmets!. The new series also welcomes Good Omens and His Dark Materials actor Ariyon Bakare, Irish actor Caoilfhionn Dunne, Foundations Evelyn Miller, the aforementioned Rylan Clark and Julie Dray, and is set to feature Rose Ayling Ellis, though we couldnt spot her in this montage.New Looks for the DoctorA close-fitting black spacesuit, a very sharp city banker-style bowler hat and pinstripe suit, some beige uniform-like space pyjamas, a natty 1950s-style suit with a pink bow-tie, a dashiki-style top and a new hairdo in an episode potentially set in Nigeria (and likely written by Nigerian playwright and poet Inua Ellams MBE, making his Doctor Who screenwriting debut this series), and, of course, a pair of tartan trousers the Doctor has a whole new wardrobe for his series 15 adventures.Doctor Who returns to the BBC and Disney+ on April 12.