Murder on Tour College professor, Clayton Rosmer is a lady killer in the old-fashion sense of the term - his charm attracts most women like a magnet. Attorney Kate Graham, however, is more interested in the scenery of the deluxe bus tour they are on, an exotic journey from Madrid to all the major towns in Spain. Kate even gets a special souvenir delivered to her door: a magnificent Moorish dagger. Several nights before leaving for home, Clayton is discovered with Kate's dagger buried in his chest. Her only excuse is that the dagger must have been stolen. In order to avoid a permanent vacation in a Spanish jail cell, Kate investigates everyone on the tour. The killer of the Lady killer is willing to continue his murderous reign in Spain - unless Kate reveals him mainly on the plain!