“An Adventure in Space and Time” (Friday, 9 p.m., BBC America)
Celebrating the 50th anniversary of Doctor Who — and the imminent arrival of new Doctor, Peter Capaldi — this docudrama tells the story of William Hartnell, the first actor to play the alien. Make a whole weekend out of it as the “The Day of the Doctor,” 75-minute movie, airs the following day and will be shown at the same time as it airs in England, so all of those British nerds on the message boards can’t ruin the plot for you.
“Marvel’s Agents of S.H.I.E.L.D.” (Tuesday, 8 p.m., ABC)
Not only are they forcing us to watch this misbegotten series to keep up with what the Avengers do on their off days, but now they’re forcing us to watch that new Thor movie to follow the aftermath on this series. It may go against every comic book geek’s core belief, but there comes a time when you have to let a story end.
“Nikita” (Friday, 9 p.m., The CW)
After three years, the super sexy, super spy begins her final six-episode mission. At the end of last season, the sci-fi geek’s fantasy was framed for assassinating the President, so she’s on the run this season. Maybe she and Brody from “Homeland” should team up.
“Ravenswood” (Tuesday, 8 p.m., ABC Family)
In what has to be the shortest season ever, this new entry gives us a “midseason finale” after just five episodes, although they were able to pack a supernatural punch in those few (turns out Nicole Gale Anderson’s Miranda died in the pilot’s car crash and ended up a ghost). “Pretty Little Liars” cast member Ashley Benson is back as Hanna, Caleb’s (Tyler Blackburn) girlfriend, who should really read the writing on the wall: When your boyfriend leaves town to star in a new series, it’s over.
“Haven” (Friday, 10 p.m., Syfy)
Oh Syfy, you always feel the need to overcomplicate things by creating an entire universe for your characters to live in so that any casual viewers are overwhelmed by the amount of information and back story they must learn just to understand a single episode. So now the social media half of this series — a “reality series” a la “Ghost Hunters” (conveniently on the same network) that has been researching the admittedly screwy town of Haven — crosses over onto the show, with Kris Lemche and “That ’70s Show”’s Danny Masterson and playing the investigating team.