The unpredictable path of four couples going through the adoption procedure is the subject of a major new TV documentary this autum.

Making Families is a landmark observational series which, says the BBC "goes behind the hype and tabloid headlines" to reveal what it is like to go through the year-long selection process of becoming an adopter.

Programme maker Sarah Johnson has been given unprecedented access for two years to four British local authority adoption agencies.

She has filmed every stage of the adoption process from applicants' first interviews with social workers, through months of questioning, training and soul searching, to the first meetings with the children and their first months as a family after the children move in.

The series follows four very different couples as they grapple with the hoops and hurdles of a process which can take years to complete.

Unrestrained by issues of confidentiality, social services departments were free to reveal what they really thought about the applicants, and vice versa.

A BBC spokesperson said: "Adoption raises many critical and universally relevant questions about family life, parenting and children's sense of identity.

"In Making Families each couple sets out on a gripping emotional journey, their destination uncertain and with incredible consequences that could never have been predicted."

The couples featured are:

Tony and Linda through Leeds social services

Linda was abused as a child and spent time in foster care. She is infertile and desperate to adopt children of her own.

But she is afraid that because of her troubled history, she will be turned down.

To her surprise the assessment process that she so feared leads her on a journey of self discovery which helps her confront the ghosts of her past.

Paula and Al through North Tyneside children's services

Both are devout Christians who are able to have their own children but, unusually, have chosen to adopt instead.

Barbara and David through Kensington and Chelsea social services

What should have been a relatively straightforward adoption turns into a traumatic ordeal for this mixed race couple as the authorities struggle to determine whether they should be allowed to adopt a baby of uncertain race.

Mark and Sarah through Kent social services

Mark and Sarah already have an adopted Romanian son and now want a second child from China. Like most adopters, they want a perfect baby.

In addition to the first series of six 50-minute films for BBC1, there are plans for one 50-minute follow-up programme to show how the families approved for adoption fared in the turbulent first two years after their children move in.

The programe is part of the BBC's £189 million autumn package which also sees a major new drama series, Care, about one man's efforts to come to terms with the abuse he suffered while in care.