Infectious endophthalmitis is an ocular infection caused by bacterial or fungal organisms involving intraocular tissues, aqueous, and vitreous humour. Bacillus sp. is an uncommon microorganism causing endophthalmitis. We describe a teenager who presented with a self-sealed corneal laceration, cataractous lens, and evidence of a breach in the anterior capsule. The eye was initially quiet and stable. The event started 1 day after uncomplicated cataract surgery. The patient developed fulminant postoperative endophthalmitis with a fatal final visual outcome. A high index of suspicion is mandatory, and more aggressive treatment may be able to improve the final outcome.