D contracted with R to the effect that D would procure a concert to be performed by his wife. D said if R paid D, his wife would perform. His wife became seriously ill on the specified date. Had she gone on with the recital, her life would've been in serious danger. R suffers losses and sues D. The Court held that D was not liable as it was frustrated by his wife's illness, because both parties must have assumed that the performance would only take place if his wife was fit to perform. As reasonable men must have intended, the contract was terminated.