10 Doctor Who Moments Deeper Than You Think
2. Fixing, Mixing, Rickston, Brixton
As Donna's brain begins to buckle under the weight of the Doctor's knowledge, she starts babbling about how to fix the chameleon circuit, famous Charlies, and rattles off a selection of similar-sounding words: "Fiction, friction, fixing, mixing, Rickston, Brixton".
Try saying that ten times fast.
It's extremely easy to miss because of how fast Donna speaks, but one of those words has a deeper meaning you might've missed.
"Rickston" actually appeared in the 2007 Christmas special Voyage of the Damned. He was a cruel and selfish narcissist who escaped the disaster of the Titanic completely unscathed, while good people like Astrid Peth gave their lives to save others.
During the pandemic tweetalong for The Stolen Earth/Journey's End, Russell T Davies revealed that Donna's reference to "Rickston" was to emphasise the tragedy of her story. RTD described Rickston as a "bad man who survived, bad thoughts in the DoctorDonna's head".
In other words, Donna's head is full of negative thoughts that will eventually consume her. This also hints at something the Doctor has always known - that sometimes, the wrong people survive. The Twelfth Doctor says as much in Flatline, when Fenton - the prejudiced and callous probation officer - survives his encounter with the Boneless.
Sadly, good people like Donna are sometimes punished for trying to be heroes, so let's hope RTD will finally give the DoctorDonna her reward in the 60th anniversary specials!