Dengue is an endemic viral fever transmitted by mosquitoes that may be asymptomatic or cause a nonspecific flu-like illness. The disease's most severe manifestations are dengue hemorrhagic fever and dengue shock syndrome. Various atypical manifestations have been observed that constitute the expanded dengue syndrome. Although uncommon, it is now known to cause cardiac complications that can be life-threatening and difficult to diagnose. We illustrate a case of a 16-year-old boy infected with dengue who experienced syncope, dizziness, and lethargy. His electrocardiogram showed third degree atrioventricular block which did not resolve with atropine and fluid resuscitation. After excluding all possible causes of complete heart block, transvenous pacing was done. A detailed workup was carried out that favored a diagnosis of subclinical myocarditis leading to complete heart block. The patient did not regain a normal rhythm and was considered for permanent pacemaker implantation. Myocarditis, pericarditis, rhythm disturbances, first- and second-degree atrioventricular blocks, and rarely third-degree heart blocks have been seen in dengue patients. However, a case of dengue illness associated complete heart blocks that is irreversible and necessitates a permanent pacemaker has never been described in the literature, and this is the first such case being reported. This article intends to increase clinicians' awareness, particularly those in dengue-endemic regions, about better recognition and comprehension of cardiac problems associated with dengue fever.