Mystery death of Thelma Todd . Police are still trying to solve the mystery of the death of Thelma Todd , the blonde film actress who recently worked in England and whose body was found slumped over the wheel of her car in the garage of Miss Todd ' s home at Santa Monica , California . The cause of death was carbon monoxide poisoning from the fumes of the car ' s engine . Miss Todd ' s death occurred shortly after she had attended a party as guest of Mr Stanley Lupino , the British actor . Murder was suspected . Photo shows , Thelme Todd ' s cafe in Santa Monica , California scene of her death . 26 December 1935