Aside from using aliases, Orchard made little attempt to conceal his activities.

During the day, the put the fireplace back together to conceal their activities.

That they were up to no good was evident by the care they'd taken to conceal their activities.

But they made no effort to conceal their activities.

That would seem to be an extraordinary revelation, telling the Russians they can no longer count on night or bad weather to conceal their activities.

Why go to such amazing lengths to conceal your activities on Earth?

According to prosecutors, the marital privilege cannot be used by joint participants of a crime to conceal their activities.

Perhaps he lived in the night, when darkness concealed his activities.

The kind that folk used when they wanted to conceal their nefarious activities.

That said, he went to considerable lengths to conceal his activities.