Neil Cross's second episode for Series 7, Part 2 dares us not to hide in the old Calaban House, where on Night 4, November 25, 1974, at 11:04 p.m., the Doctor and Clara join an anxious pair of ghost hunters hoping to a show the lonely and lost soul that abides in the place the way home. "Calaban House is over four hundred years old," but the Calaban Gast "has been around much longer"—and, as the four soon find out, there's more to this ghost—this Wraith of the Lady, Maiden in the Dark, Witch of the Well—mentioned in local Saxon poetry and parish folk tales, than a simple ghost story.

"Boo! Ha ha. Hello. I'm looking for a ghost."

"And you are?"

"Ghostbusters."

The ghost busters would be the Doctor and Clara.

The ghost hunters are: "Major Alec Palmer, member of the Baker Street Regulars, the Ministry of Ungentlemanly Warfare—specialized in espionage, sabotage, and reconnaissance behind enemy lines…, a talented water-colorist, a professor of Psychology;" and "Emma Grayling, the Professor's companion… assistant, and non-objective equipment—meaning psychic."

Learning that the music room is the heart of the House, the Doctor and Clara quickly set out to find the ghost—because "ignorance is… um… what's the opposite of bliss?" Pursued by something unseen—hiding in the dark—they reach the pantry at 12:55 a.m. and the music room a short time later.

"Do you feel like you're being watched?"

"What does being watched feel like? Is it that funny tickly feeling on the back of your neck…? Then, yes; a bit. Well… quite a big bit."

The Doctor discovers a spooky cold spot.

Clara is not happy.

Her candles go out. The entire House grows cold. An very loud angry knocking is heard. She's coming.

Startled by something behind them, the Doctor and Clara race downstairs, where a Phantom-Zone-like portal hovers before the ghost hunters/busters and Emma experiences a powerful, empathic psychic connection.

Developments convince the Doctor that he's not going to solve the riddle of the Calaban Gast sitting still. He needs to go always—to try to capture the ghost through a series of snapshots every few million years.

The snapshots reveal that the Calaban Gast isn't a ghost at all, but is a lost soul—a pioneering time traveler from the future named Hila Tacorian, trapped in a pocket universe. And she appears to be running from something.

Using a subset of the Eye of Harmony (see "The Deadly Assassin, "The Invasion of Time," and 1996's Doctor Who), a blue crystal from Metebelis III—which Actor Matt Smith mispronounces—twice (see "The Green Death" and "Planet of the Spiders")—and some sturdy rope, the Doctor prepares to enter the pocket universe and rescue Hila with Emma's help.

Emma opens the portal. The Doctor dives in. Hila is rescued. But the Doctor is now trapped—with the something.

From deep within the TARDIS the Cloister Bell sounds.

Clara races to the Blue Box, but, again (see "The Rings of Akhaten"), finds the "grumpy old cow" locked.

Emma reopens the portal just as Clara convinces the TARDIS that they have to help the Doctor and just as the Doctor comes face-to-face with a Crooked Man inside the pocket universe.

Day saved.

Almost.

As the Doctor reveals the Hila could be the great-great-great-great-great-granddaughter of Emma and Alec, he realizes "every lonely monster needs a companion."

"It's the oldest story in the universe—this one or any other: boy and girl fall in love, get separated by events—war, politics, accidents in time. She's thrown out of the house or he's thrown into it. Since then they've been yearning for each other across time and space—across dimensions. This isn't a ghost story. It's a love story."

Back into the pocket universe to rescue the Crooked Man.

Day saved.

Great Lines

Doctor: "I'm the Doctor."

Alec: "Doctor what?"

Doctor: "If you like."

Doctor: "I like the word toggle. Nice noun. Excellent verb."

Doctor: "So where's the ghost? Hah? Show me the ghost. It's ghost time."

Clara: "Doctor?"

Doctor: "Yes?"

Clara: "Shh."

Doctor: "..."

Doctor: "I'm giving you a face. Can you see me? Look at my face."

Clara: "I've got this weird feeling it's looking at me—it doesn't like me."

Doctor: "The TARDIS is like a cat: a bit slow to trust—but you'll get there in the end."

Clara: "So I am a ghost. To you, I'm a ghost. We're all ghosts to you. We must be nothing."

Doctor: "No. No; you're not that."

Clara: "Then what are we? What can we possibly be?"

Doctor: "You are the only mystery worth solving."

Emma: "What did you see?"

Clara: "That… everything ends."

Emma: "No; not everything. Not love. Not always."

Emma: "What does it do?"

Doctor: "It amplifies your natural abilities. Like a microphone. Or a pooper scooper."

Clara: "You're talking, but all I can here is 'meh meh meh meh meh.'"

Alec: "What about us—Emma and me…? Well… what's supposed to happen? What do we do now?"

Doctor: "Hold hands. That's what you're meant to do. Keep doing that. And don't let go. That's the secret."

Also see the Doctor's remarks about the Crooked People near the end of the episode—included above.

Wibbly-wobbly Timey-wimey… Stuff that You Might Have Missed

The opening shot of the episode—of a gnarled tree—may be meant to foreshadow the appearance of the Crooked Man at the end of the episode.

There are a lot of 11s in Night 4. November 25, 1974. 11:04 p.m.—including in the month, in the year (7 + 4 = 11), in the time, and in the night/day (4 + 2 + 5 = 11). There are also a lot of 4s in there too—3 of them, which add up to 12. And according to Clara, "whiskey is the eleventh most disgusting thing ever invented." (For more numerology, see "'The Bells of Saint John' Reviewed.")

Clara's "Ghostbusters" is another 80's reference (see "'Cold War' Reviewed"). The 1984 film of the same name featured the tag line "I ain't fraid of no ghosts," which hardly seems to describe Clara after learning that the Calaban Gast is "actually real." Of note, the Clara introduced to us as the end of "The Snowmen"—who, incidentally, appears to be clothed and accessorized very similarly, if not identically, to the Clara in this episode—remarks, "Nah. I don't believe in ghosts."

Clara again carries her red bag and wields a red umbrella in the episode. The Doctor uses a red balloon in his demonstration. The dark room is bathed in red light. Red is the color of love, a fact that may be important in the context of the Doctor's remarks near the end of the episode about the Crooked People—which one might conclude are remarks about himself as well (just as Alec's remarks to him in the dark room also clearly echo the Timelord's past).

While Clara and Emma talk, the Doctor helps himself to some milk (see "Asylum of the Daleks").

The Doctor's sonic screwdriver may be in need of an tune-up. Or a replacement (See "Silence in the Library").

A "subset of the Eye of Harmony" (see "The Deadly Assassin, "The Invasion of Time," and 1996's Doctor Who) remains within the TARDIS—suggesting that the Eye itself may have been spared Gallifrey's fate during the Time War.

The well is likely the portal between universes.

The TARDIS has used holograms to communicate with others before: first, in "The Parting of Ways" and, again, in "Blink" in the new series. In both cases, the TARDIS selected the Doctor's image.

Clara is, apparently, not only able to communicate with the TARDIS on some level, but to pilot it by herself as well.

Also consider this: what, exactly, is hidden in the episode?