Doctor Who: 10 Clever Moments Of Foreshadowing You Probably Missed
3. The Absent Sister
Steven Moffat's first contribution to NuWho was the terrific Empty Child/Doctor Dances two-parter, a story that cemented the phrase "Are you my mummy?" into the nightmares of many a young fan.
These episodes revolve around the mystery of the creepy gas mask child, and as we later learn, this child's real name is Jamie. Though he's framed as a villain, he really doesn't mean any harm - his only goal is to track down his mum, Nancy, which he successfully does at the end of the second episode.
But because Nancy has spent the entire story telling everyone that Jamie is her brother, the fact that he's her son is treated as something of a twist reveal - a reveal that was foreshadowed by an easy-to-miss visual cue in The Doctor Dances.
At the start of that episode, the Ninth Doctor and co. break into Jamie's room, which contains dozens of childish drawings littered around the place. These drawings all depict the same thing: Jamie's mother, crudely etched in crayon.
Most importantly though, what isn't depicted in these drawings is Jamie's older sister, who Nancy claims to be - but of course, that's not true. The fact that Jamie only draws his mother is a clue that Nancy was lying about her relationship to him.