From aliens in the wi-fi to a brain leech under a hat, from some bad nannying to a trio of idiots with a really big space magnet, it’s been an odd half-season for our favorite Time Lord. Here’s our recap of the second half of series 7 of “Doctor Who.” Plus: The Spoiler Horn makes it safe for everyone who wanted to learn the Doctor’s real name. Host Jason Snell with Chip Sudderth, John Siracusa, Dan Moren and Scott McNulty.