The answer is Pope Francis on a bike, a prospect made tantalizingly possible by the pontiff's latest gift.
Francis was presented with a customized racing bike on Wednesday by three-time world cycling champion Peter Sagan, who dropped off the bicycle during a visit to the Vatican.
The speedy-looking two-wheeler came in the papal colours, gold and white, and was emblazoned with "Francesco".
Peter Sagan (centre) with the Pope's bike. Photo: Andreas Solaro/AFP
The Slovakian cyclist, who attended the Pope's weekly audience in St Peter's Square, also offered the signed jersey he wore as world champion.
This is the pontiff's second pedal-powered Popemobile: in 2015, during a visit to Philadelphia in the US, he was presented with a more sturdy model by local bike makers Breezer. They also donated 100 bicycles to community programmes in the city.
They're the least flashy, but most eco-friendly, of the various vehicles that the Pope has received as gifts, which include a Harley Davidson motorcycle and a Lamborghini sports car.
He had both vehicles auctioned off to raise money for charity.