DIANA: DESIGNING A PRINCESS, BBC2, 8pm

WHEN Hilary Mantel said Kate Middleton was simply a fashion clothes horse, the usual suspects were outraged over this slight on the fair maiden.

Of course, Mantel was making the point that the royals seek out young, well-bred women to produce heirs and look pretty: the barb was for the system, not the pretty Duchess.

Anyway, she was right. Much of “princessing” is about being styled and dressed, not about opinions and intelligence.

Wills wouldn’t have married an ugly girl: she’s got to look good in a gown.

And so it was with his famous mother, Diana, whose fashion choices were always scrutinised.

This programme shows the effort and calculation which goes into putting togs on a toff.

The show looks at some of Diana’s most famous dresses as they’re prepped for an exhibition, and we see how she used dresses to silently communicate her feelings, such as wearing the daring “Revenge Dress” the night Charles admitted his adultery.

TABOO, BBC1, 9.15pm

IT’S the series finale tonight and I’m sure we’ll all be sorry to see this drama end.

It has certainly spiced up Saturday night TV, which is normally weighed down by talent contests, glittery game shows and constant Casualty.

Taboo was the antithesis of such repetitive, predictable nonsense, bringing Gothic darkness to all the maddening primary colours, singing, dancing and cheering of Saturday night telly.

Even if the plot was sometimes rather too complex and mysterious, you could still enjoy the drama for its forbidding atmosphere, content to soak it all up in its black, muddy glory until the storyline peeped through and became gradually clearer.

Tonight, there’s a showdown between our hero and Sir Steven Strange.

After all his torture and agony, Delaney still has the energy and the rage to confront his enemies.