A Is for Acid (2002)

Dramatisation of the true story of the notorious "acid bath murderer" John Haigh, who murdered women and disposed of their bodies in vats of acid in the 1940's. He was only caught when the gallstones of one of his victims, Mrs Durand-Deacon, failed to dissolve in the acid and were detected by the pathologist who examined the residue from the acid bath.