Thirty million Indians want a job on the railways, but a fiendish general-knowledge test stands in their way. Could you “Explain America’s policy on Huawei.”? Do you know the answer to “Who propounded the homeopathic principle ‘like cures like’?”?

In the city of Patna, the capital of India’s second-largest state, an entire industry has developed to cater to Indians desperate for a shot at a stable career. Reporter Dipanjan Sinha travels to Patna to meet the pupils and teachers gambling on India’s railway lottery.