World champions Russia lived up to predictions that they would cement their dominance of synchronised swimming at the London Games, claiming the title for duets with a crisp routine inspired by horror movies and macabre fairytales.

Natalia Ishchenko and Svetlana Romashina - in costumes decorated with dolls, their eyes framed by toy-like eyelashes - took gold after scoring 98.9 points out of a possible 100 in the free routine executed for the final.

That marked an improvement on Monday's score for the same sequence and took their total points to 197.1 - more than four points clear of their nearest rivals Spain.

Russians, bringing a tradition of ballet to the pool, have taken home the Olympic gold for duets since Sydney in 2000, earning a reputation for seamless execution in a sport that demands precision and endurance - paired with a smile.

Spain's tango-inspired routine helped their duo to silver, retaining the same medal position as in Beijing four years ago. China came 0.03 points behind with their dragon choreography as they took bronze.