It's a sample in a Dreadzone track called "Heat the Pot". I knew it was Eric Idle's voice but had no idea where from, or in what context he'd said it.
Watching The Ruttles: all you need is cash the other day, and there it was. It's a Beatles story mickey take and they'd got to bit bit that equivalent to John starting on LSD and the lot of them going to see the be-robed chap (sorry, bit vague on the Beatles).
Anyway, I'm glad I've cleared that up. Moving on to the next life-changing thing….