4. Mum

As Cameron Finnigan is sentenced at the Old Bailey his mum speaks out. She offers a rare, painful and deeply revealing insight into families caught in the fallout of 764.

The BBC investigation explores what it will take to stop this network and the National Crime Agency reveal what they’re doing to combat the growing threat of online groups like 764.

Written and Produced by Jo Palmer.

For information and support on issues discussed in this series, visit bbc.co.uk/actionline.