The book the Secret Garden is one of my all time favourites and the video of the book is superb so I bought "Back to the Secret Garden" hoping for more of the same. I was extremely disappointed.
Misselthwaite Manor is now an orphanage run by Mary (who married her cousin Colin). Colin is made Ambassador to the USA and so Mary ships off with him and a sick orphan who needs treatment only available in the US, leaving Martha in charge at Misselthwaite. For some bizarre reason, it seems that Mary must send an orphan from the US back to Misselthwaite in exchange for the one she took to the US. This orphan, Lizzie, hears about the Secret Garden and wants to find out more. Martha however doesn't think the kids should be allowed in (except on Sundays after church for ettiquette lessons) and keeps it locked the rest of the time. Lizzie steals the key to get in the garden... and it all goes downhill from there.
The writer of this story, Joe Wiesenfeld, seems to have missed the whole point of the original novel by Frances Hodgson Burnett
and captures none of it's magic.
Probably watchable if you haven't seen the original (that's the only reason I gave it 1 star) but if you're a fan then don't waste your time (and money).