When Henry comes home from school and finds a strange baby hidden among Aunt Agatha's hollyhocks, it looks as if another adventure is in store - especially when little Sweetheart sprouts antennae! But when a host of dark, ghostly women begin to haunt 131 Ballantyre Road, all desperate to catch a glimpse of the baby, Henry and his new friend Rosie know this is another job for the magical, marvellous Harvey Angell. Henry's extraordinary friend quickly realises that Sweetheart isn't from this world - she's from the future, and she needs to get back there before it's too late. That means a trip through time for Harvey Angell - his most breathtakingly dangerous mission yet .