La Mercè and Culture Festival of Stockholm (this year's guest city) have jointly produced the show that will be projected on the facade of City Hall. It's a creation by audiovisual communication studio NueveOjos, which has developed the script with David Lillo, of the Central Attic of Screenwriters. For the first time, the 'mapping' at the Mercè takes the form of a fictional story. The project, directed by Mariona Omedes, tells a love story between two buildings where it will be screened: Barcelona's City Hall in Plaça Sant Jaume and Arvfurstens Palats, home of the Swedish Ministry of Foreign Affairs. Catalan illustrators have also collaborated on the project.