Of all the one-on-one character dynamics in The Big Bang Theory, there are few as interesting or entertaining as the two-hander between Sheldon and Penny.
Though they couldn't be much more different in many ways, that hasn't stopped fans "shipping" them since the show's early days, and wondering quite whether that fiery chemistry could've become something more in another life.
But of course, Sheldon and Penny ultimately stayed just friends and that was probably for the best. Instead, we got to see their initialy frosty friendship bloom into something truly loving (and platonic!).
Pretty much every single episode of the series boasted at least one memorable, hilarious exchange between the two, but just how well do you remember some of their most iconic moments together?
Yet because we wouldn't want to make it too easy for you, you'll need a massively over-the-odds knowledge of Sheldon and Penny's friendship to get 100% on this quiz. As we go along, each question becomes trickier than the one before it, so don't let those easy earlier questions lure you into a false sense of security. This will get tricky.
But fear not no matter how you do, because the answers are at the end as ever. Good luck!