The Secret of the Kloog — Margaret Pearce

Mike's father goes missing on a remote island. Mike, Alinea and Beeper travel through a time gate to find him.

He is unconscious, they have to protect him during their desperate search to return home, escaping being dumped at the Intergalactic lost property, and illegal dealers who want them silenced, and still stay away from the Kloog.

An odd creature the Quok, that Beeper distrusts, is the only one prepared to help them. When they arrive on the mysterious 'Place of the Call' they realize that Beeper's distrust of the Quok is scaringly well founded.