While McDonald's has done curry burgers in some Asian countries (like Japan and Hong Kong) in the past, it's a little bit rarer for more western, European market (which is not to say they've never done it and they do offer a curry sauce for dipping in some countries like the UK).
Like much of the value menu, the new Curry Beef and Curry Chicken sandwiches veer towards sweet simplicity. Each features either a beef or crispy chicken patty along with a spicy curry sauce and sliced onions on a regular hamburger bun. They go for 1 Euro each.