The Moon at Noon — Jule Owen

A door in time. A visitor from the future. A girl determined to save the boy she loves.

The third book in the mind-twisting dystopian time travel series, 'The House Next Door'
Mathew Erlang travels north through an England overrun by violence and sickness. Accompanied by a new friend, he finally makes it to his grandmother's house, but all is not as it seems in this childhood place of safety. Meanwhile, Clara makes an uncanny pact with Mathew's peculiar neighbour and finally learns the truth about Mr. Lestrange.