Emily Burdick, the kid daughter of brilliant but eccentric mathematician Ethan Burdick, is kidnapped, yet he sends the police away, even Charlie Eppes, who he respects scientifically, as soon as he hears FBI agent Don Eppes is his brother. This time maths may well be the problem: Ethan claims to have solved the elusive Riemann-hypothesis, a very prestigious challenge involving prime numbers, worth a major award, so a rival may want to steal it and/or sabotage him...
—KGF Vissers