The Sniper of Escondida

Book 3 of 5 in the Treasure of Escondida mini-series.
"With Lara and the rest of the team still reeling from recent events, they meet with the King to learn the true contents of the treasure room. Lara’s attention is diverted when she notices the red laser of a sniper’s sight. Trying to keep calm, she watches it dance on the wall in a figure eight. It could only be one person: Sam, a long-time competitor who signals her in the castle for a meet."