Sean and Melissa, a brother and sister detective team, investigate some thefts and mysterious electrical disturbances at their father's radio station.

Sean and Melissa learn not to be afraid when God is on their side as they investigate a string of robberies in which the only suspect is an invisible knight.

Sean and Melissa continue their sibling banter even as they are caught up in a dangerous search for a treasure hidden somewhere in the old, supposedly haunted, church that the town is planning to auction

When Scott and Melissa Hunter and their dog, Slobs, are hired by lonely, eccentric Mr. Carlson to investigate the UFO he believes he has seen, they learn more about the true meaning of friendship for Christians than they do about space aliens

When a vampire torments the people of their town, Sean and his sister Melissa use their detective skills and depend on the help of God to deal with the problem

When a visiting troupe hypnotizes some of the people of Midvale and a mysterious string of robberies ensues, Sean and Melissa use their detective skills to find the thief

When the residents of Midvale believe a phantom car is terrorizing their town, Sean and Melissa use Biblical teachings and detective skills to find the real culprit.

Panic grips Midvale when a mummy disappears from an Egyptian exhibit at the museum, leaving it up to Sean and Melissa to solve the mystery.

After a strange lady curses the town of Midvale, a series of mishaps has everyone worried, until Sean and his sister Melissa can figure out what is really happening.

When their friend Bear gets involved with a group of school misfits who model themselves after a popular fantasy book series, Sean and Melissa go undercover to reveal the truth about their "magical powers."

Book 11 of Bloodhounds, Inc.. A popular pop group comes to Midvale, and all the teens are excited. Also, there seem to be messages coming from outer space. Are they connected?

With the help of a new invention from Doc, Sean and Melissa win an all-expenses-paid trip to Washington, D.C., where they hope to solve the mystery of a missing helicopter—and of a haunted hotel.