I ended up reacting to this book much as I did to Ruth Ware's Woman in Cabin 10. I felt compelled to keep listening and listening until I got to the end, but once I was done, I wondered why I'd spent all that time.
The "lying game" of the title doesn't ultimately seem that significant to the central "mystery" of the book. Although Ware tries to make the lying game relevant to the lie and cover-up the four former boarding-school classmates share, I think she fails at that. The lying game was all about fooling classmates or teachers to believe their lies--the more of a "whopper" the better. But the conspiracy of silence between main-character Isa, Fatima, Thea, and Kate was to protect Kate, and had nothing to do with their whoppers.
There was also just so much that was implausible. There was a "scandal" that resulted in the girls being given a choice between expulsion and leaving voluntarily, and they all opted for the latter. But it's ridiculous that the girls are blamed for the "scandal." There is a scene where the school's current headmistress says the situation would be handled completely differently "today," but you'd think the "scandal" had taken place in the 1950s, instead of being in 2000 or thereabouts.
Isa is supposed to be a lawyer, but it's hard to believe she had the intelligence to become one. And her grasp of criminal law seems fairly shaky. There were times when I'd be thinking "Don't do that--it's so stupid and dangerous!" Then she'd acknowledge that it was stupid and dangerous. So you know better, but do the stupid, dangerous things, anyway? Including endangering your baby? Excellent.
If you were "meh" about The Woman in Cabin 10, and you are hoping The Lying Game will be an improvement, you may want to take a pass.