Their operation, from what we know, relies on speed and surprise.

The success of the mission would depend on speed and surprise.

For a moment her face was entirely blank with neither protest on it nor surprise.

We'll come back for you, but our mission depends on secrecy and surprise.

Since the eagles depend on surprise to make a catch, this frequently causes them to leave the area.

There was a chance that the attack, based on speed and surprise, might succeed.

The plan depended on total surprise being achieved to avoid the Iraqi forces.

For the rest, he would have to depend on luck and surprise.

But he still counted on confusion and surprise to aid him.

I think that the power of therapy depends on novelty and surprise.