Clan Rebel. Highland Heroes, #3

Only three members of the Last Division remain after Lily Barnett and Jaimee Abernathy disappeared into an alternate dimension beyond the time portal. Now Echo Boxwood and her two remaining comrades must travel back through time in a last-ditch rescue mission to save not just their missing friends but all of human history from disaster. Elliot Ritchie has been trying to hide from the ghosts of a haunted past, but it all catches up with him when Echo shows up and offers him a temptation he can't resist.
When a confrontation between him and the Buchanans goes disastrously wrong, Elliot will have to dig deep to find the courage, tenacity, and honor to make things right, not just with the Buchanans but with himself and his estranged brother Grant. When Echo challenges him to seize the reins of his life, they'll both have to fight with all they have to build a world where war doesn't threaten to tear them apart and destroy the love they've worked so hard to win.