Immigration is a tricky enough subject to even discuss with like minded people without becoming entangled in a web of contradiction and absurdity, so it is no doubt even trickier to make a film about.

The danger to avoid is getting preachy, and the key to doing so is to stick to the story and let the sequence of events and the characters and let the audience think for itself.

In this respect, 'The Visitor' is a masterclass.

The film begins with a relatively long establishing sequence that brilliantly brings the central character, Walter Vale (Jenkins), to life. Vale, an ageing economics professor, is moulded in the viewer's mind in the space of a few beautifully constructed scenes; a piano lesson, a brief, rude, encounter with a student, and a short talk with a colleague coalesce to make us feel as though we know everything about him, and everything he might do in a given situation.

In fact, the character of Walter is so stuck into his inert existence that you begin to wonder where the film can go. Gently and slowly, though, the story starts to happen, and Walter is lifted from his austere, hypocritical and lazy lifestyle.

Forced by his university hierarchy to go to New York to deliver a lecture at a conference, he is catapulted into a new set of circumstances. He discovers Tariq (Sleiman) and Zainab (Gurira), illegal immigrants from Syria and Senegal respectively, living in his apartment. After initial difficulties, a friendship develops. Tariq introduces Walter to African music and gradually, his withered personality and humanity are re-awakened.

Just as things seem to be improving, chance intervenes for the second time. Tariq is gobbled up by the immigration system. Walter feels involved, drifts away from the arid theory of the economics scene, and becomes increasingly committed to helping. Needless to say, the grim realities of the immigration landscape are laid bare and, because the audience has already identified with Tariq, it is hard not to feel an empathy for his plight.

But there is much more to this film than that. Behind these events are a number of cleverly layered strands and references. Contrasts, humour, complexity and intricacy are never far away but despite this the film manages to feel naturalistic without being dull.

Partly, that is because of the superb performances. Richard Jenkins’ nuanced portrayal of Vale is particularly outstanding. Hiam Abbass, who plays Tariq's mother, is also excellent.

Are there any downsides? Well, this is not an epic film, and perhaps doesn't reach the heights on the emotional register that it might have done. For better of worse, emotional grandstanding is by and large eschewed in favour of a more quietly pitched vibe.

In fact, 'The Visitor' could arguably be said to be 'overcrafted'. For some it may feel as though it suffers from an ever-so-slight lack of emotional 'oomph', and a sense that it is almost too 'just ruffled enough' perfect, although that is a minor quibble.

In the end, 'The Visitor' is one of the most rewarding and thought provoking films you will see this year.

Brendan Cole