Dubbed Mothy Knickers in high school, for being a bookish nerd, Timothy Funicular prefers to be known as Tim Fun in later life
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Enrolled in the Australian Police Force, clever Tim Fun qualifies as a detective. His surfing hobby has him act as a lifeguard when off duty.
Shy and reserved, Tim Fun gains his 29th year without ever attracting a steady girlfriend. The few girls from his surf club who accept dinner dates only use him as a meal ticket.
Tim suspects he is being set up for a laugh when precocious teenager Xanthe Bridcombe attempts to seduce him as her first lover. Tim does his best to put the 16-year-old girl off.
When Xanthe's younger sisters play a prank on Tim he is placed in a more compromising situation. The girls' big burly father Sergeant Angus Bridcombe takes a dim view of shenanigans.
During Tim's eventful year, he faces embarrassing and life-threatening problems.
On top of it all, Tim Fun falls desperately in love with Xanthe Bridcombe who, at sixteen, is thirteen years his junior.