Behnam describes the failure of his electric shower, which was a top-of-the-range model costing £600 but malfunctioned and eventually exploded due to an electrical fault likely caused by a faulty isolator switch. He explains the symptoms including strange noises, burning smells, and eventual fire damage. Behnam replaced the shower himself with a cheaper model bought on Amazon for about £215, finding the installation easy and safe after switching off electricity. Janice praises his DIY skills.