The Adventurer: The Curse of the Midas Box (2014) looked like a fun, light-weight boys-own adventure - heck, it's almost in the title. And it came through.
The story is set in a late Victorian steampunk era. A pair of Oxford antiquities professors, the Mundys (Ioan Griffud and Keeley Hawes) and their sons Mariah (?) and little Felix run into adventurer Will Charity (Michael Sheen), who brings news of a map, then disappears. When their parents disappear, the boys go on the lam. Felix is captured, leaving Mariah and Will to find him, the parents and the mysterious McGuffin, the Midas Box.
First of all, Mariah is played by Aneurin Barnard, a rather odd looking young man, with dark, brooding eyes, like something out of Gormenghast or The Sorrows of Young Werther. Or Morrisey played by Elijah Wood. He adds the Goth to the steampunk. Then there's Michael Sheen, who camps around as a kind of Arnold Rimmer as Dr. Who (David Tennant version). We also get Sam Neill as the evil Otto Luger and Lena Headley as the bitchy hotelier, Monica. All played with gusto, in great period clothing. Sheen, in particular, is a bit of a bohemian fop, with high collars, top hats and a jaunty corncob pipe. But Barnard gets to dress up when he goes to work as a hotel page.
About half the story takes place in an island hotel and spa, very steampunk, with lots of glass, elevators cages, cast iron balconies, etc. Very Grand Hotel Budapest. The whole movie was clearly made possible by inexpensive CGI, but we liked the look.
Now, the story was pretty silly. People appeared and disappeared as needed. Mysteries that vast conspiracies couldn't solve are figured out by a smart teen in an instant. There could have been more steampunk, more magic, more action or even more romance (Barnard has a love interest in freckled Mella Carron). But if you aren't expecting much, you might get it.
In conclusion, the McGuffin is OBVIOUSLY a sampo!