Mysteries thicken around the Alden children's mission to return a trove of stolen artifacts in this updated reboot of the classic series.The second episode of a five-volume arc picks up right where the first, Journey on a Runaway Train (2017), leaves off—taking Violet, Jessie, Henry, and Benny first to Cairo and the pyramids, then to Nairobi, Stonehenge, and finally on to Rome. At each stop except the last they return an ancient figurine or other small treasure taken from the locale while also touring archaeological sites, encountering giraffes, riding camels, foiling elusive thieves, solving riddles, receiving cryptic texts and email messages from unknown parties, and wondering why their expected contact Tricia has suddenly gone on the lam. The new authors tuck in summary infodumps designed to fill readers in on the Aldens' long history and the current scenario, but this outing ends as abruptly as it starts and leaves its all-white central cast entangled in unresolved conundrums. Caveat lector. On go the Aldens from one exotic locale to the next, through experiences more exciting than dangerous. (cast gallery, afterword, bio of original author) (Adventure. 8-10)