Eat a full kilogram of cow-candy by the river
Officially opening today on the part of the Southbank overlooking Parliament, Gillrays is the sort of place that will nonetheless give you red if you ask for blue: a steakhouse housed in a curved space whose plush, Art Deco-y vibe is reminiscent of a gentlemen's club... from back in the days when that unfortunately meant just what it sounded like.
Hailing from the Duke of Devonshire's estate, the beef is dry-aged for 35 days, then cooked at each doneness-level's ideal degree (they provide a chart to edify you on that), whether bone-out (fillet, rib eye, D-rump) or -in, e.g., as with the monolithic "Bull's Head": a full kg of double-rib steak that, despite being butterfly cut, will metamorphosize you into something a little less beautiful.
If you've a beef with cow, or just need a break to make sure your love for it is true, go for anything from Devon crab cakes & Cornish oysters w/ Champagne vinaigrette, to bigger stuff like Billingsgate fish, or smoked pork chops sided by crushed King Edwards, who just found out that Braveheart makes them out to be total a-holes.
Getting you in the mood to become a one-man apocalypse for the animal kingdom's a cocktail list that, along with some classics, leans on 40+ all-Brit gins and some tea tinctures to produce the likes of the The Morning After Marriage (Hendrick's, Assam & rum) and the Hayman's 1820/gunpowder green/Cognac/whiskey Gunpowder & Smoke -- though whatever you liberally indulge in, it'll all come out yellow.