Nate the Great and the Mushy Valentine — Marjorie Weinman Sharmat

Nate the Great hates mushy stuff. But when he spies a big red paper heart taped to Sludge's doghouse, Nate knows he must help his favorite pooch. Who could possibly have left Sludge a secret valentine?

It's a mystery until Nate finds out that his friend Annie is missing a valentine. The case seems simple. Nate is relieved. No more mushy stuff. That's what he thinks....