Gilderoy Lockhart made fame look easy. The public always saw him smiling, impeccably dressed, and holding his newest published book. The public thought he was always up to another heroic act, or writing his next book about one of his adventures. They were partially right—he was often working on writing a book—but they were mostly wrong—not a single one of the heroic deeds he claimed were actually his.
While he may only admit it to himself, Lockhart knew he was a coward, and his ability, strength and speed of spellwork just were not good enough for him to survive doing what he'd claimed to do. But he could not just make things up—it was too easy to check the existence of monsters at certain places and times for him to do that. No, what he spent the most time doing was research, trying to find situations he could exploit before they could become generally known. But it seemed like no one had been quietly doing heroic deeds lately…
Which lead to his present situation. What fascinated wizards and witches just as much as dangerous adventures with a handsome hero? The baby hero who saved them all, Harry Potter. If Gilderoy could get his name attached to the Boy-Who-Lived, he'd be set for life. Especially since the Wizarding World had rarely even seen their hero in seven years—Dedalus Diggle was the talk of England for weeks and got a heavy commission from the Daily Prophet for his story, when he managed to bow and greet the Boy-Who-Lived while shopping for groceries.
Gilderoy couldn't just greet Harry Potter, of course, but spending the day would work, especially if he could be the first to show the boy the sights of the Wizarding World. While the eight year old would undoubtedly be curious enough about his parents' world that Gilderoy would easily be able to get him to come, no vaguely responsible guardian would let their charge go with a stranger alone, just on the stranger's say-so and the Ministry was sure to have wards on the house to alert them if a wizard snooped around for too long.
Luckily, he had the perfect solution for that—Memory charms. He'd created enough memories of days, weeks, and in one case—months of actions and interactions that a couple of weeks of "getting to know, be charmed by, and coming to trust" memories would be a cinch! He would just need to remove some memories of them sitting at home without visitors first, to place the created memories in.
So, Gilderoy used the stories of those who had seen the Boy-Who-Lived to track down his family. He was a bit surprised by what little he saw—Harry Potter's uncle was a whale—but said Uncle was, luckily, sleeping outside when Gilderoy arrived. He grabbed the chance.
One meter from the whale's head, the spell fizzled out and died. Gilderoy Lockhart stared, shocked, and then tried again. When that spell also died, he started to worry, and sent a quick barrage of obscure, easily reversible spells—and they all died the same distance away. He'd never heard of a ward that acted like this—he certainly was not able to deal with it, and the ward might be monitored and its flares noticed. He needed to get out of there before it was too late and instead try something else.
He'd heard mutters about a werewolf two days back—maybe he should look into that.