They wake from this second dream with Santa's help -- but, surprise, they're still in a dream. There are four sleepers in the base's infirmary and four other crew members... but everything points to their only being four crew members at the base. The sleepers and the crew members are, in fact, the same people, and everyone has been in a shared dream all this time.
They're saved again by Santa, who picks them up in his sleigh ("Fortunately I know all of your home addresses"). Now, one by one, they wake to find themselves back in their own lives.
What About Clara?
This episode is a bit odd where Clara's concerned. It's been barely two months since we last saw an episode of Doctor Who, and Clara looks just as we remembered her -- but throughout the episode, there are moments where she acts like it's been a much longer time. She's at a complete loss, unable even to speak when she first sees the Doctor again, not convinced he's real. When she's first on the TARDIS, she comments about how much she loved the noise it made. And at the end, in the sleigh, she gives the Doctor a long hug before he wakes and stays sitting by Santa for a long while, not wanting to wake up herself. This could be all about Danny, but it feels like it's been a much longer time for Clara than it has been for the viewers at home.
It's explained when the newly-awakened Doctor rushes to Clara's to free her from the crab, only to find her an old woman. The resulting scene is very sweet, with the two of them celebrating Christmas quietly together, with paper hats and Christmas crackers, while Clara talks about her life. It's reminiscent of last year's Christmas special, in which Clara celebrated with an aged Matt Smith. Capaldi's Doctor is awkward trying to do the family togetherness thing, but it's precious to watch him try.
It's would have made a lovely swan song for Jenna Coleman's Clara Oswald, who'd been much-rumored to be leaving the show. "We should do this every Christmas," the Doctor says... which leads to Santa Claus walking in, the Doctor waking up again and rushing to save Clara again. This time when Clara awakes, she's her younger self again and both Clara and the Doctor decide to make up for their dream-regrets by traveling together again.
It's great to see Clara sticking around after the character development she's gotten over the last season, but this ending feels like it undercuts the emotional moment that came immediately before it... and it would honestly make more sense if it were a last-minute addition. But if it was, no one's saying so. We'll see Capaldi and Coleman again in season 9 of Doctor Who, which doesn't yet have an exact air date, but we can expect to see it some time in 2015.
Bottom Line: Sure, the episode has flaws, but it's balanced out with some truly great show moments. Plus: Nick Frost as Santa Claus.
Recommendation: "Last Christmas" is a solid episode of new Who, with a dose of sci-fi, a dose of Christmas cheer, a few scares, and some genuinely emotional moments. We'd tune in for this episode, even if you haven't been a fan of the Capaldi era to date.