The fic starts when Thor fails to recognize Natasha when she comes in from an assignment. She's dyed her hair a dark color, and Thor thinks she is an intruder, tackles her and she manages to pin him. The other Avengers finally manage to convince Thor that it really *is* Natasha, even though Thor remains suspicious.
Another time, Pepper helps Jane get ready for a big date with Thor -- new clothes and everything -- only Thor doesn't recognize Jane when she is "dressed up."
One of the last times is when Loki hijacks the tv networks dressed in a 'Thor' costume and proceeds to upset Thor by dancing the Macarena, the Chicken Dance and finally, karaoke.