Imagine a slower-talking Pat-rick Moore crossed with an athletic version of Magnus Pyke, put him on a mountain bike in a yellow and pink Day-Glo outfit and you've got some sort of picture of Adam Hart-Davis.
For six weeks he's been searching out his "local heroes" - scientists and inventors who achieved astonishing feats in their day but many of whom are now forgotten.
While Hart-Davis fulfils many of the "mad boffin" criteria, he's also an enthusiastic and imaginative teacher. The series takes in many scientific principles and presents them vividly through historical figures. Best of all, though, are Hart-Davis's wonderfully improvised Heath-Robinson-type experiments which, miraculously, seem to work. His re-creation of Brunel's "atmospheric railway", for example, used cardboard tubes, two vacuum cleaners and a lot of Post-it stickers and managed to propel him forward 50 metres or so in a rickety cart. In the background was the vast pumping station which helped to propel the original railway.
Then there was the gleeful visit to the vicarage of the Rev Henry Moule who invented the earth closet in 1859. Here Hart-Davis showed us buckets of (simulated) excreta, illustrating the effect of dry earth on it before constructing his own makeshift earth closet.
On he cycled to Lyme Regis and the fossil shop which the humble and un-eductated Mary Anning packed with the discoveries which were to pave the way for Darwin's Theory of Evolution.
Up in Scotland, his first Scottish hero was Alexander Bain - hopeless shepherd and hopeless student - who in 1843 patented the electro-chemical telegraph, which could send pictures or printed words along telegraph lines - a forerunner of the modern fax.
Hart-Davis recreated the original invention - using DIY shelving units, 12 tins of baked beans, batteries and a electro-magnet. He managed to transmit a faint but recognisable image of Alexander Bain from "Wick" in one corner of the room to "London" in the other.
Later he made a Mackintosh by putting into practice the Scottish inventor's recipe for a rubber sandwich which would keep out the rain; and in honour of the great but not famous physicist James Clerk Maxwell, he took a successful colour photograph of himself in a fetching multi-coloured kilt - using blue, green and red filters and black-and-white film.
Adam Hart-Davis can fire even non-scientific imaginations by his sheer exuberance and eclecticism. Many of his experiments would make wonderful catalysts for a wide variety of science groups. It is a shame, though, that he has not been given more time to develop each character study. Sometimes the programmes can seem more like a frenetic version of Yesterday's World.