Quickly, he climbed the ladder and stepped on to the roof, giving Lex a quick glance to see if she was okay before scanning the areas in front and behind him. Nothing, nothing, nothing, moving shadow. Which turned into a person who froze as soon as he saw Drake. Bingo. Drake grinned and took off, knowing that Lex would follow him soon enough.
There wasn't really anywhere for the guy to go, which was good because Drake really didn't feel like jumping from roof to roof in pursuit of the guy, and he wasn't even sure if Lex would be able to follow if it had come to that. Instead, it looked like the suspect was just going to run side to side on the roof.