Lisa wrote time-travel trilogy, The Hourglass Door, which I had seen somewhere a while ago. I bought all three books since she signed them and carried them in the airport (they were heavy) and just finished the third book, The Forgotten Locket.
Abby is a high school senior ready for adventure when she meets and falls in love with Dante, a prisoner sent from fifteenth-century Italy into the present time, when they work together on their school play. But Zo, another prisoner, has dark plans that threaten everyone.
Click here for the link to buy the book if you’re interested; I highly recommend reading it.