Throughout I kept thinking, is this how I would want a professional carer to look after my mother, sister or partner? Making this judgement is neither easy or comfortable.

Tim Roth plays David, a nurse who specialises in the care of dying patients in their homes. During the course of the film he looks after four different people and bathes, feeds, dresses, supervises their medication and helps them in and out of bed.

So far so good, but when we see the almost sensual way he washes the first patient, Sarah (Rachel Pickup), an emaciated, now non-verbal woman in the final stages of her illness, her helpless body held slackly against the wall as he sponges between her legs and later when she dies hoisting each leg onto his shoulder using tender, long, slow strokes to wipe her down, my alarm bells started to ring. What if this was my sister?

Stranger things begin to happen too. As David sits at a bar nursing a drink after Sarah's funeral, he tells a woman who strikes up a conversation with him that his wife of twenty one years has just died of Aids and the funeral had been that day...

We then see David working with his second client, John, who has just had a heart attack. After a very successful life as an architect he now struggles to enunciate and is partially paralysed. David becomes not only very involved in John's physical care but his whole life. In a shop David pretends he is John as he buys books to share with his patient about architecture. He then knocks at the door of a house which John designed and tells the owner he is John's brother and would like to look at the finished home.

The film causes you to constantly ask yourself, why does David do this? Is he aware of the boundaries between professionalism and intrusion, interest and obsession, detachment and over-involvement?

When fellow agency relief carers take over from David at the end of his shift the difference between their cool, professional approach and David's assumptions of intimacy become even more glaringly obvious and I certainly started to feel very uncomfortable when David sent home the night carers, spending the time holding his patient’s hand while he sleeps and finding John pornographic films to watch, crisply slapping shut the laptop lid whenever a relative comes into the room.

Yes, John enjoys the films but is this entirely harmless? More details of David's past emerge. His former marriage to Laura (Nailea Norvind) are revealed in oblique fragments, as David re-establishes contact with their college-age daughter Nadia (Sarah Sutherland) and the tragic circumstances that broke up the family also come slowly to light.

Whilst Roth’s persistently dour yet sincere portrayal of David stops him being seen as an out and out pervert, you can tell he sincerely believes he is doing good and is truly dedicated to his work. However, I never stopped wondering about the motivations driving him, the impact of his obsessive need to be wanted and become the most important person in his patient’s lives.

Inevitably John's family suspect something is not right as David continues to not only exclude them from the sick room as he (innocently?) eases his way into number one position in John's life. They make an official complaint to the care agency of sexual harassment on behalf of John, and when David's manager calls him in and says he 'Cannot afford another lawsuit' David returns to his home area to look for another client.

So it is at this point you would expect David to reconsider his approach to patients, to learn from the warnings and at least be counselled or mentored by the agency while being suspended pending a full investigation, but no. David still gets work as a carer for the terminally ill. How or why this is allowed to happen is not revealed.

Despite sympathy for David's personal experiences I certainly was alienated in the second half of the film as nothing seemed to change. David still goes running, pounding pavements or the treadmill in the gym, he moves onto two more vulnerable patients and inserts himself once again into to their very personal lives. I was desperate for it all to end. And end it does, abruptly. And some would say very unsatisfactorily. In a split second you are left alone with your concerns, your conclusions. The final judgement can only be yours, but maybe that's the point?

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