The latest episode of Doctor Who's 13th season, also known as Flux, had everyone enthralled and confused by revelations about the Doctor's old enemies, the Weeping Angels.
But, that wasn't the only surprise the episode had in store for us. As the episode flipped between the Doctor's battle with the Angels and new character Bel (Thaddea Graham)'s search for her long-lost love Vinder (Jacob Anderson), we were introduced to someone that we have definitely seen before – but not in Doctor Who.
Blake Harrison, perhaps best known as Neil from The Inbetweeners, appeared as Bel arrived on the planet Puzano looking for Vinder, and is saved by Bel from being trapped inside the Ravagers' passenger form, which we found out about in 'Once, Upon Time' last week.
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Introducing himself as Namaca Ost Parvess Po after convincing the initially-distrustful Bel to put her gun down, he invites her to a gathering (a coalescence) where someone will be able to get them to safety and away from the Flux. But, when Bel accompanies him there, she finds the Ravagers 'abducting' people into the Passenger forms and drags Namaca away with her.
Though he is angry at first that she cost him a chance to join the Passenger form, he later says that she "saved [his] life". He also helps Vinder receive a message from Bel, setting the course for the two to finally find each other as we approach the end of season 13.
People on Twitter were shocked to see The Inbetweeners' Neil on the show, with one person tweeting: "I'm actually losing it over the fact that Neil from The Inbetweeners is now officially part of the Doctor Who universe."
Related: Doctor Who: Flux reveals plot, title and cast for series finale
Though Harrison only appeared for a short time, his role in facilitating a potential reunion for Bel and Vinder was much appreciated, as people are loving the storyline between them. One person wrote on Twitter, "All I want for Christmas is for Bel and Vinder to find each other."
People are also speculating as to what Bel and Vinder's role in the overarching story is, theorising that they might be the Doctor's real parents. But we will have to wait to find out.
Doctor Who: Flux (aka series 13) airs weekly every Sunday night on BBC One in the UK. In the US, the show airs on BBC America, with series 1-12 available on HBO Max.
For more information on Doctor Who: Time Fracture, head this way – tickets are also available via retailers including LOVEtheatre, London Theatre Direct, Fever and Ticketmaster.