Prince Charles famously described a planned extension to the National Gallery as a ‘monstrous carbuncle on the face of a much-loved and elegant friend’. Two decades on, and architects Wilkinson Eyre seem to be mocking The Heir with revamp plans that appears to include a swollen pustule erupting on the facade of the Science Museum.

And here’s a close-up:

The excrescence bulges out from behind the fluted columns to reveal a museum that’s “full to bursting with energy and ideas”. I love it. The Science Museum is far and away the most architecturally anonymous of the three South Kensington Museums. For a classical building It could scarcely be more bland. This bold intervention provokes curiosity, pulling the passerby inside to discover more. The galleries will also be remodelled with the addition of a new ‘skyspace’ – a gilded rooftop space dedicated to cosmology.

The plans come on the 100th anniversary of the museum. If they go ahead (and these things are never certain – ask the V&A), the scheme should be complete by 2014.