Film Actors work with the Director to create believable characters. They must be able to learn their lines quickly, and to retain their meaning and inflection, while sometimes repeating the same scene many times over, for re-takes, and while scenes are shot from different angles.

Actors should also know their fellow Actors' lines, so that they can respond to them accurately and appropriately. They need to remember their exact positions and movements at any given time during the performance, to assist with continuity. They must also be able to continually hit their marks on set, without looking down to locate them.

Actors must be infinitely adaptable, as they may find themselves portraying many different characters over a short period of time. They must be aware that others contribute to their characterisation, e.g., those working in the Make Up, Costume, and Design teams, and that they may be serviced by a host of others in terms of transport, catering, etc.