location shooting in Germany, which took place during the 2006 FIFA World Cup. Facundo Arana and Natalia Oreiro played their characters in the Veltins-Arena stadium during the Argentina-Serbia and Montenegro match. The result of the matcha 6–0 Argentine victorybenefited the filming, and the episode received 31.5 rating points. Location shooting also occurred in the tourist ski resort Las Leñas in the Andes. A simulated aircraft crash that left the characters in a jungle was filmed at the Pereyra Iraola park and an Argentine Air Force park in Morón. To make her performances as a female boxer look realistic, Oreiro trained regularly with the renowned boxer Marcela Acuña and her coach Ramón Chaparro. They taught Oreiro how to stand and move in the ring and how to make various types of strokes, and she underwent cardiovascular and weight training. Acuña commented that Oreiro mastered the basic techniques more quickly than most beginner boxers. For this training, Oreiro temporarily gave up her vegetarian diet. Another plot required the characters to fly a Piper Tomahawk airplane and make an emergency landing. This was risky filming, and Arana and Oreiro did not use stunt doubles for it. The scene, which was the first of its kind in a daily Argentine telenovela, required four professional pilots, five special effects experts, and two additional aircraft used for filming the main aircraft from the outside. Arana was advised by the pilot Alberto Di Giorgio. The program's opening theme is Gilda's "Corazón Valiente" (), sung by Oreiro. It was produced by Toti Gimenez, widower and producer of the late Gilda. Oreiro is a fan of Gilda and chose this song as a homage to mark the 10th anniversary of her death. She considered including it in her next music CD, but did not record anything afterwards. Guest actors The program featured several guest stars, who appeared in secondary or support roles in several episodes. Some guest starssuch as the singers Chayanne, Ricky Martin and Julieta Venegasplayed themselves within the fiction of the program. Venegas' song "Tu Nombre" is used as a background song in romantic settings. Marcela Acuña appeared twice, playing herself in a match against Oreiro's character. The appearance of actress Leticia Brédice was nominated for the "best cameo in fiction" category at the Martín Fierro Awards; the prize was given to Nora Cárpena. Actress Reina Reech delayed other projects to take part in the program. Narration