Tammy Vance was an actress.
History
As a child, Tammy Vance played Mary Dahl's big sister Susie on Love that Baby. As an adult, she was an accomplished actress and appeared in Death of a Salesman with co-star Brian Daly. The night after Daly went missing, two armed crooks abducted Miss Vance by force; they were able to successfully elude Batman, Robin and the police.
Tammy was reunited with the rest of the cast at the studio where they had filmed their television program. Mary Dahl revealed that she planned to remake the Birthday episode from years earlier wherein she was upstaged by Cousin Spunky. This time, however, she planned to use a candle that was actually dynamite and kill everyone. Robin, disguised as Spunky, managed to prevent the explosion and the hostages were released.