Can someone give me a trick question, or a brain teaser to solve, or something like that?

Newly married couple drive off to their honeymoon . Along a country lane the car runs out of fuel ...the groom says to his bride that we only just passed a filling station and would set off to get some. He told his bride to lock the doors until his return . Upon his return the car is exactly as he left it ...no damage or break in at all ...inside the car is a Stranger ...and his wife is dead ..... how did she die ? ....and who is the stranger ?