Did you spot the sneaky scientific Jon Pertwee reference in Doctor Who: It Takes You Away?

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“What if you do something it hasn’t dealt with before – like you reverse the polarity or something?” offers Mandip Gill’s Yaz, little knowing how appropriate that information is.

“Yasmin Khan – you speak my language,” the Doctor replies – and she’s not wrong. During his time on the series, Jon Pertwee’s Doctor often suggested that he or others “reverse the polarity” of some piece of technology, partly because Pertwee had asked the writers to give him easier technobabble to spout during the episodes.

In time “reverse the polarity of the neutron flow” became something of a catchphrase for the series, entering the popular culture perception of Doctor Who, though Pertwee only actually said that particular version of the line once.

Since Pertwee, a few other Doctors have used the phrase (including Tom Baker’s Fourth Doctor, Peter Davison’s Fifth, David Tennant’s Tenth and Matt Smith’s Eleventh), so really the Thirteenth Doctor should have remembered exactly the solution she needed.

And when we combine this callback with all the Venusian aikido we’ve seen Whittaker’s Doctor use this year, it’s looking like a pretty nostalgic time for fans of the Third Doctor still watching Doctor Who.

All we need now is a return for Bessie the Whomobile…

Doctor Who continues on BBC1 on Sundays

This article was originally published on 2 December 2018