Frankie Bridge of the Saturdays is on a mission to track down internet trolls whose abuse can devastate their victims. She talks to former X Factor singer Chris Maloney, who received a barrage of death threats, and Denise Fergus - the mother of two-year-old Jamie Bulger - who reveals she has been trolled by cruel individuals taunting her about her son's murder 23 years ago. Frankie has also received an onslaught of hurtful harassment but is refusing to take it lying down. With the help of a team of IT experts, she now knows some of their identities - and intends to hold them accountable.