That’s bright! It’s got bright red and black striped warning colouration. It’s the Bee-Eating Beetle, Trichodes apiarius, named by Linnaeus in 1758.
According to UK Beetle Recording (yes, there is such a thing), “This small family includes 14 species recorded from Britain, all of which are local, rare, or probably extinct here.”
The species Trichodes apiarius and another, “Have not been seen since the 19th century and are likely to be extinct.”
The adults of the Bee-Eating Beetle lay their eggs in the nests of solitary bees or in the hives of honey bees, and when the grubs hatch they eat the larvae and nymphs of the bees.
Here in Italy, in the warmth of the sun, watching the adult eat pollen, I’m glad that it’s not extinct here.