My 1982 380SL was taken for a ride and parked, then about an hour later refused to start.

The instrument panel shows lights (as well as the headlights), indicating battery power but nothing happens with the turn of the key - not even a clicking sound.

The first thought would be the neutral safety switch but there never was a tendency for that to act up - unless it has simply failed.

Any thoughts? I need help on this one.