Orphans Pauline, Petrova and Posy Fossil are adopted by eccentric explorer Professor Matthew Brown ('Gum'), and raised as sisters by his selfless niece Sylvia. When Gum goes missing, Sylvia makes ends meet by taking in lodgers, whose actions change their lives forever. The girls are enrolled in theatre school and put to work on the stage. This suits ambitious Pauline who longs to act, and Posy, a natural dancer, but Petrova, who longs to be an aviator, suffers great frustration and disappointment. Life in showbusiness is shot through with triumph, but hearts are broken and lessons learned before Gum returns and ensures a happy ending for all.