Irish authorities are investigating the links between an Irishman, Mark Mulligan, and Holly Willoughby's stalker, Gavin Plumb, who was convicted of plotting to kidnap, rape, and murder the TV presenter. Gardai seized electronic devices from Mulligan's residence in Dublin after Interpol's tip-off and found exchanged messages discussing the kidnapping plot. Plumb had gathered items for the crime, including restraints and torture tools, causing immense fear and distress to Willoughby. Mulligan, previously convicted of stalking, engaged with Plumb on the Kik app and is now under criminal investigation. The ongoing probe involves examining the disturbing messages between the two culprits planning the heinous act against Willoughby.