A top-drawer cast tells writer/director Stuart Blumberg’s intelligent and challenging story about people obsessed with an excessive behaviour driven by naturally-occurring chemicals that all humans produce in greater or lesser degree.

The story unfolds around a self-help group tormented by sex addiction, using methods similar to those for alcohol, tobacco or narcotics addiction. It’s an interesting concept deftly developed in the film.

Mark Ruffalo plays businessman Adam, celibate for five years. No copulation, no auto-eroticism, no exposure to temptations beyond those that commerce plasters on posters all over the city. A tough gig, but Adam’s comfortable with it after addiction wrecked his marriage.

Mike (Tim Robbins) is addicted to helping addicts recover. His marriage to Katie (Joely Richardson) has been blighted by the disappearance of their son (Patrick Fugit)

Chubby medico Neil (Josh Gad), not blessed with overt sex appeal, with a sex addiction that could lead him into professional and legal trouble, discovers a possible path to salvation when he meets barber Dede (Alecia Moore, a.k.a. Pink), sexually addicted since childhood.

The emotional response of Phoebe (Gwyneth Paltrow) to a double mastectomy is to dislike the rest of the world. Until she meets Adam.

This mix of relationships and emotional factors in a gently involving blend of drama, comedy and romance works pretty well on all levels. Watching it on the twelfth anniversary of quitting smoking cold turkey had a special resonance for me.

AT Palace; Capitol 6; Dendy