All four of C. J. Tudor's novels have been Sunday Times Top 10 bestsellers. The fifth is her most twistiest and chilling yet

A crashed coach full of students.
A stuck cable car full of strangers.
An isolated chalet full of friends.
A killer snowstorm outside.
Inside one group, a killer.
But which one?
And why is no rescue coming?
How did they become trapped?
And what were they all trying to escape?