Each of the stairs up to the bedrooms was made out of a slab of absolute black granite. He checked the glass- smooth surfaces as he moved slowly upwards. Nothing. The floor at the top of the stairs was made of black granite inlaid with diamonds of white marble. He was drawn to the door of the master bedroom. The double bed was occupied. A pillow lay over the face of the occupant whose arms lay outside the light duvet on the bed. There was a slim band of a wristwatch on an arm flung out as if reaching for help. A single visible foot had bright-red toenails. He went to the bedside and checked for a pulse while looking down on the two depressions in the pillow. Lucia Vega was dead, too.

There were three other rooms upstairs, all with bathrooms. One was empty, another had a double bed and the last belonged to Mario. The ceiling of the boy's room was painted with a night sky. An old, one-armed teddy bear lay face up on the bed.

Falcón reported the second dead body to Juez Calderón. The Médico Forense was kneeling by Sr Vega's side and working at prising his fingers apart.

'There seems to be a note in Sr Vega's right hand,' said Calderón. 'The body's cooled down quickly in the air con and I want him to get it out without tearing it. Any first thoughts, Inspector Jefe?'

'On the face of it, it looks like a suicide pact. He's smothered his wife and then drunk some drain cleaner, although that's a nasty, lingering way to kill yourself.'

'Pact? What makes you think there was an agreement?'

'I'm just saying that's what it looks like,' said Falcón. The fact that the little boy was left out of it might indicate some collusion. A mother wouldn't be able to bear the thought of the death of her own child.'

'And a father could?'