Amhránaí mór le rá í Bianca Castafiore, Éan Ceoil Milano mar a thugtar uirthi. Nuair a thugann sí cuairt ar an gCaptaen Haileabó i Radharc na Mara, scaiptear ráfla go bhfuil focal is lámh eatarthu, rud a chuireann an Captaen ar buile. An chéad rud eile, tá na meáin ag triall ar Radharc na Mara agus nuair a sciobtar seoid luachmhar an amhránaí – smaragaid – tá ina rírá ceart. Cuirtear an milleán ar na Giofóga ach ní dóigh le Tintin gurb iad na Giofóga na coirpigh sa chás seo. Cás casta, cás thar a bheith suimiúil!

Bianca Castafiore, the world-famous diva, visits Capten Haileabó at Radharc na Mara. The tabloid press pick up on a story that she and the Captain plan to marry, and soon the Captain’s home becomes the centre of media attention. As the news hacks search for newsworthy nuggets, Bianca Castafiore’s priceless jewellery become centre stage in this intriguing adventure. Castafiore’s most treasured emerald goes missing, and accusations are rife as Tintin and the police try and identify the thieving culprit. Will the diva’s woes be assuaged by the search for her most glittering jewel?