Convenient Horse

The use of a conveniently placed object within a movie scene to advance the plot, specifically related to the majestic white horse on the shores of a cliff side castle in "Snow White and the Huntsman" conveniently awaiting snow's arrival to them ride off down the coast together

Wow, that chick from outlander knows a shit ton about plants for a military nurse, it's a pretty fucking conveinent horse that her husband just happens to be doing a genealogy project on that specific time period of Scotland that she gets thrown into, I mean fuck.

The convenient horse of this scenario is that the character Just happens to know so much about this random period of a country that she isn't from, and knows a lot about herbal medicine even though she was a nurse of a more modern time.