Lord Percy Percy, heir to the Duchy of Northumberland, was a fictional character, played by Tim McInnerny, in the popular British sit-com Blackadder. In fact, he was two fictional characters, the Lord Percy of Blackadder II being the descendant of that seen in The Black Adder. Unlike the first two Blackadders and Baldricks, the two Lord Percys are almost identical.

Incredibly loyal yet incredibly stupid, Lord Percy is described by Lord Blackadder as 'a dimwit I can't seem to shake off'.

Lord Percy is a caricature of an English, upper-class twit, obsessed by the frivolities of his age. These include neck ruffs of varying sizes (the largest making him look like 'a bird who's swallowed a plate', according to Blackadder), dressing like half an allotment in Nottingham Forest to celebrate the return of Sir 'Rather A Wally' Raleigh, collecting religious artefacts (which are largely fraudulent) and archery — in one episode he declares 'I would like to see the Spaniard who could make his way past me!', Blackadder suggests he should go to Spain, where there are millions of them.

Lord Percy is also the inventor of 'Green'. He discovered this particular entity whilst working on alchemy. The only real fundamental difference between green and gold is that green is green rather than gold, it comes in 'splats' rather than nuggets and it has no value whatsoever.

Lord Percy has something of a dislike of Baldrick. This is perhaps as a result of the fact that, despite his higher social status, he still receives the same amount of affection (or lack thereof) from Blackadder. This was particularly true in the first series, when Percy was intent on looking down his nose at Baldrick, however, this is rarely of any avail as Baldrick is much more intelligent than him. By the second series this appears to have largely subsided (perhaps because Baldrick is now closer to his intelligence level) and the two appear to be quite friendly (Lord Percy at one point snogs Baldrick, believing him to be a bridesmaid). However, there are still signs of the Lord Percy's distaste towards Baldrick, as he is reluctant to count him in on the money he plans to make by fashioning 'Green' as jewellery.

Lord Percy only appeared in series one and two of Blackadder, as Tim McInnerny was worried about being typecast. However, McInnerny did have a small role in series three and returned as a different character — Captain Kevin Darling — in series four. Presumably for this reason, while both Blackadder's Christmas Carol and Blackadder: Back & Forth return to the setting of Blackadder II, neither features Percy.

In a scene that was filmed for the final episode of the first series but not used, Percy identifies himself as 'Lord Percy Percy, seventh son of the seventh Duke of Northumberland'. This and most of the other location scenes for the series were filmed in Hulne Park, Alnwick, Northumberland, at that time in fact the property of Hugh Algernon Percy, tenth Duke of Northumberland. The castle that appears in the title sequence and in location shots throughout the series is Alnwick Castle, home of the Percy family since 1766.