Jo, it seems, is the only survivor out of the bank siege after bank manager Cliff Sniffton who'd been repeatedly abused by Eddie (Rhys Ifans) and Ian, suffers a psychotic break, and proceeds to slaughter both surviving robbers and hostages alike.
Later it's shown that one of the thieves (and her father) Maitland (John Hurt) also survived and escaped by smuggling himself out in a body-bag. Cliff, who winded up locked in the vault (by Maitland), violently greets corrupt cops Insp. Badger and D.I Guffin (who come to steal the money).
Aided by Prof Corner, Maitland reunites with his daughter Jo in a morgue and leaves with a body-bag stuffed with cash.
Thanks ND Woods!