The Big Bang Theory

The slow progression in Sheldon’s relationship with Amy occupies a special position on television. Their baby steps are like strides between continents in other love stories, but they’re all the more tender for it. This episode the couple decide to buy a pet turtle, but it’s Sheldon’s failure to tell Amy that he’s applied for a mission to Mars that yields the biggest development.

Leonard and Penny are rather more athletic in their activities, and Raj gets into trouble with Emily when he goes snooping. Stay tuned for a brief tribute at the very end to Leonard Nimoy (Star Trek’s Mr Spock), who died a week before the US transmission. Big Bang never forgets its heroes.