Black tie, as it is worn in Britain now

Hire is often the right first answer. The second answer is alteration. A shawl collar on a man with a short neck is a different garment to the same collar on a man with a long one. We cannot recut a hire jacket as we would a owned one — but we can set the trousers, the shirt, and the waistcoat so the whole does not shout “collected yesterday”.

If you own the jacket, we can go further. Sleeve, suppression, a proper trouser braid line. That is when black tie stops being costume.