Quakes recorded for the first time inside Greenland's biggest frozen river, the Northeast Greenland Ice Stream, suggest this river and others switch between moving jerkily and flowing like honey.

See an exclusive clip of Best Actor Oscar nominee Timothée Chalamet as Bob Dylan singing 'Song to Woody' in 'A Complete Unknown'.

The magic of movies and television usually relies on careful planning, choreography, and a lot of safety measures on set.