Mrs. Cornell appeared to be an elderly tourist, who was in reality the wanted criminal Lefty Callahan.
Physical appearance[]
She looked like an elderly woman with white hair which was in a semi-large beehive-shaped hairstyle, pink lipstick and circle-shaped glasses. She's dressed in a dark green blazer and skirt, as well as a light gray top underneath. She was also shown wearing light gray high-heeled shoes and a matching purse.
Personality[]
She appeared to be both friendly and considering, telling another visitor off for scaring Shaggy and Scooby with the legend.
History[]
Scooby-Doo and Scrappy-Doo (first series)[]

Lefty Callahan revealed.
She first appeared when she, the gang and another visitor named Sally Polk visited Alcatraz Island, where she took part in the guided tour on the island. She later returned to the mainland with the others and stayed at their hotel because she needed to rest so she could visit the opera later. Finally, she appeared after the vampire had escaped capture by the gang at the opera, where Velma unmasked her to reveal she was actually the vampire, who in turn was actually Lefty Callahan, who had used both disguises so she could retrieve the jewels she stole.