[TriLUG] Data vanished from a partition?

[Tom Bryan via TriLUG]

I'm hoping that someone has some suggestions because my search fu has
utterly failed me on this one.

My wife's laptop runs KUbuntu 14.04.  When she rebooted and logged in
earlier this week, none of her files were there.  At first, I just
assumed that the home partition, /dev/sda7, simply wasn't mounted.  I
found that the partition *was* mounted, but it was apparently empty.
It still has a filesystem on it.  Since she has an account on the box,
KDE helpfully created a new home directory with the normal default
files and folders when she logged in.  And those files persisted just
fine.

I haven't been able to find any big errors in the logs or anything.
It's like someone did a /bin/rm -rf /home/*.  So, I now have a
partition that looks like a normal ext-4 partition.  It no longer has
any of the files that it had last week.  It also has the new skeleton
of a home directory that KDE just created.

I've seen hard drives get flaky and start to lose data or fail to
mount.  But I've never seen anything like this.  Basically, everything
was there when she shut down.  When she started the machine up an hour
later, it was all gone.

And, of course, I did something that broke automated back ups months
ago.  I'm really hoping that someone has some suggestions here.  :-(
Has anyone ever seen anything like this?  Other than running fsck on
the partition from a LiveCD, does anyone have any suggestions?

---Tom