In terms of believable reality in teenage fiction, you're not really going to get much out of the Hardy Boys. Stuck in a sort of time warp where the heroes, brothers Frank and Joe Hardy, are 18 and 17 respectively, and have been since the first book was published in 1927, we have seen them travel virtually all over the world, solving crimes that seem to have thwarted various countries' law enforcement specialists.

The Hardy Boys' adventures normally involve them being sought out to find amissing person, retrieve stolen goods or stop the occasional international spy ring. When they are the ones approached by someone else, it drops the believability even more. However, the boys' father, Fenton Hardy, is a renowned supersleuth, and his rep is often passed down to his boys, who haven't failed to solve a mystery yet! Every now and then, along comes a mystery that Fenton is deeply involved in, and the boys jump along for the ride.

This is one such tale, only this time dad has gone missing, and the boys are a bit fearful for his safety. They are investigating the theft of a diamond in Washington, (as you do!) and when they realise that their dad could be in danger, they soon sniff out the trail, which turns out to be wrought with danger.

The Infinity mark starts cropping up in random places, and the switched oin brothers soon deduce that this has something to do with good old dad and whatever he was working on. Once again, two differing plots lines verge into one in a Hardy Boys book as the two eternal teenagers set out on their own personal missing persons hunt.

The Hardy Boys books were favourites amongst teenage boys throughout the majority of the 20th Century. The first 20 or so books are considered the cream of the crop, particularly since they were revamped in the 60s and 70s to bring them a bit more up to date. All Hardys books are published under the pseudonym Franklin W Dixon, but are actually written by a series of ghost writers employed to carry on the good work of early ghosts such as Leslie MacFarlane.

In terms of characterisation, a small amount of the book is given over to the boys, although there is no elaborate character description from book to book, there having been so many books previous to this one that the characters have developed over time. The same goes for other major characters who frequent the books, including Fenton. However, those who are solely in this book, particularly some of the villains, are well described and effectively put on paper.

The plot itself is quite easy to follow, and the added excitement and suspense with Fenton missing makes the plot that much stronger. You won't get quite such intensity and appeal as some of the more modern books targeting the teenage male reader, but these books are still decent reads.

The Infinity Clue is the 70th Hardy Boys book, although it is the 12th published by Simon & Schuster after they won the rights from Grosset & Dunlap in 1979. As a result, you may see this book advertised as either number. It's worth a read, as I believe all the Hardy Boys books are. They won't give you anything special, but they will give teenage boys a good adventure to read, and it is something a bit different to the current run of teenage fiction such as the Stormbreaker series, Harry Potter or Twilight.

The Infinity Clue is not so easy to get hold of in this country, but is readily available from amazon.com for a fair price.