What's the last book or item you added to your Hardy Boys collection?

[SkyWarp]

The Great Airport Mystery
What Happened at Midnight
The Sinister Sign Post
The Secret Warning
The Mystery of the Flying Express
The Short-Wave Mystery
The Secret of the Lost Tunnel
The Clue in the Embers
The Secret of Pirates' Hill
The Mysterious Caravan

[CalvinKnox]

I picked up the Harold Hill edition of "The Shore Road Mystery" at a Salvation Army in New Zealand.  I compared it to the American OT version and see that instead of hiding in their car's "locker" and eating "crackers", they hide in the boot and eat biscuits.

[tomswift2002]

I picked up the Harold Hill edition of "The Shore Road Mystery" at a Salvation Army in New Zealand.  I compared it to the American OT version and see that instead of hiding in their car's "locker" and eating "crackers", they hide in the boot and eat biscuits.

In the UK & former British Empire/Commonwealth, Harold Hill was the only publisher of "The House Om The Cliff" and "The Hidden Harbour Mystery".  Of course the artwork they commissioned was pretty Picasso-esque I find.

[CalvinKnox]

Unfortunately, my copy was well used and alas, doesn't have the dust jacket.