Giant, angry, red, subterranean spider: What could possibly go wrong?
Well, the Doctor telling Donna she’s unimportant, for one thing. Then he learns better.
I love Donna for many reasons, not the least of which is that she violates the “make the character likable” rule. Donna is not likable, you just want her around anyway. Which is why the rule should be “Make the character fascinating.” “Likable” is a dime a dozen; “fascinating” is the gold standard. Only Donna could have said one of my favorite lines from Who: “You’re not mating with me, Sunshine.”