Lacy grinned at him, taking ahold of his free hand as he pushed open the door. She could've sworn that she saw someone or something darted into the brush but put it off as it was probably a bird. 
As soon as Senna darted away, Ace touched a silver band on his wrist and turned invisible. He had a gadget that could turn make him appear as a totally different person but that was an earring he had on, so the band was the closest one. He turned around to watch Dick and Lacy, walking backwards but still following the man. 
Lacy totally disregarded the image of Ace she thought she saw. Maybe this vacation was a good idea. Being around the kids who she thought were back in Gotham had really got into her head. Anyhow, she didn't show any change in expression at the thought but rather just looked across the sunny surroundings.