On the way back to Twin Elms, Helen congratulated her friend. "Now that one of the kidnapers has been caught, I'm sure that your father will be found soon, Nancy. Who do you suppose the man was who took your father from Greenman and his friend?"
Nancy looked puzzled, then answered, "We know from his description that he wasn't Gomber. But, Helen, a hunch of mine is growing stronger all the time that he's back of this whole thing. And putting two and two together, I believe it was Willie Wharton who drove that car.
"And I also believe Wharton's the one who's been playing ghost, using masks at times—like the gorilla and the unshaven, long-haired man.
"Somehow he gets into the mansion and listens to conversations. He heard that I was going to be asked to solve the mystery at Twin Elms and told Comber. That's why Gomber came to our home and tried to keep me from coming here by saying I should stick close to Dad."
"That's right," said Helen. "And when he found that didn't work, he had Willie and Greenman and that other man kidnap your dad. He figured it would surely get you away from Twin Elms. He wanted to scare Miss Flora into selling the property, and he thought if you were around you might dissuade her."
"But in that I didn't succeed," said Nancy a bit forlornly. "Besides, they knew Dad could stop those greedy land owners from forcing the railroad to pay them more for their property. That's why I'm sure Gomber and Wharton won't release him until after they get what they want."
Helen laid a hand on Nancy's shoulder. "I'm so terribly sorry about this. What can we do next?"
"Somehow I have a feeling, Helen," her friend replied, "that you and I are going to find Willie Wharton before very long. And if we do, and I find out he really signed that contract of sale, I want certain people to be around."
"Who?" Helen asked, puzzled.
"Mr. Barradale, the lawyer, and Mr. Watson the notary public."
The young sleuth put her thought into action. Knowing that Monday was the deadline set by the railroad, she determined to do her utmost before that time to solve the complicated mystery. Back at Twin Elms, Nancy went to the telephone and put in a call to Mr. Barradale's office. She did not dare mention Comber's or Willie Wharton's name for fear one or the other of them might be listening. She merely asked the young lawyer if he could possibly come to Cliffwood and bring with him whatever he felt was necessary for him to win his case.
"I think I understand what you really mean to say," he replied. "I take it you can't talk freely. Is that correct?"
"Yes."
"Then I'll ask the questions. You want me to come to the address that you gave us the other day?"
"Yes. About noon."
"And you'd like me to bring along the contract of sale with Willie Wharton's signature?"
"Yes. That will be fine." Nancy thanked him and hung up.
Turning from the telephone, she went to find Helen and said, "There's still lots of daylight. Even though we can't get inside Riverview Manor, we can hunt through the outbuildings over there for the entrance to an underground passage to this house."
"All right," her friend agreed. "But this time you do the searching. I'll be the lookout."
Nancy chose the old smokehouse of Riverview Manor first, since this was closest to the Twin Elms property line. It yielded no clue and she moved on to the carriage house. But neither in this building, nor any of the others, did the girl detective find any indication of entrances to an underground passageway. Finally she gave up and rejoined Helen.
"If there is an opening, it must be from inside Riverview Manor," Nancy stated. "Oh, Helen, it's exasperating not to be able to get in there!"
"I wouldn't go in there now in any case," Helen remarked. "It's way past suppertime and I'm starved. Besides, pretty soon it'll be dark."
The girls returned to Twin Elms and ate supper. A short time later someone banged the front-door knocker. Both girls went to the door. They were amazed to find that the caller was Mr. Dodd, the realtor. He held out a large brass key toward Nancy.
"What's this for?" she asked, mystified.
Mr. Dodd smiled.
"It's the front-door key to Riverview Manor. I've decided that you can look around the mansion tomorrow morning all you please."
CHAPTER XIXThe Hidden Staircase
SEEING the look of delight on Nancy's face, Mr. Dodd laughed. "Do you think that house is haunted as well as this one?" he asked. "I hear you like to solve mysteries."
"Yes, I do." Not wishing to reveal her real purpose to the realtor, the young sleuth also laughed. "Do you think I might find a ghost over there?" she countered.
"Well, I never saw one, but you never can tell," the man responded with a chuckle. He said he would leave the key with Nancy until Saturday evening and then pick it up. "If Mr. Comber should show up in the meantime, I have a key to the kitchen door that he can use."
Nancy thanked Mr. Dodd and with a grin said she would let him know if she found a ghost at Riverview Manor.
She could hardly wait for the next morning to arrive. Miss Flora was not told of the girls' plan to visit the neighboring house.
Immediately after breakfast, they set off for Riverview Manor. Aunt Rosemary went with them to the back door and wished the two good luck. "Promise me you won't take any chances," she begged.
"Promise," they said in unison.
With flashlights in their skirt pockets, Nancy and Helen hurried through the garden and into the grounds of Riverview Manor estate.
As they approached the front porch, Helen showed signs of nervousness. "Nancy, what will we do if we meet the ghost?" she asked.
"Just tell him we've found him out," her friend answered determinedly.
Helen said no more and watched as Nancy inserted the enormous brass key in the lock. It turned easily and the girls let themselves into the hall. Architecturally it was the same as Twin Elms mansion, but how different it looked now! The blinds were closed, lending an eerie atmosphere to the dusky interior. Dust lay everywhere, and cobwebs festooned the corners of the ceiling and spindles of the staircase.
"It certainly doesn't look as if anybody lives here," Helen remarked. "Where do we start hunting?"
"I want to take a look in the kitchen," said Nancy.
When they walked into it, Helen gasped. "I guess I was wrong. Someone has been eating here." Eggshells, several empty milk bottles, some chicken bones and pieces of waxed paper cluttered the sink.
Nancy, realizing that Helen was very uneasy, whispered to her with a giggle, "If the ghost lives here, he has a good appetite."
The young sleuth took out her flashlight and beamed it around the floors and walls of the kitchen. There was no sign of a secret opening. As she went from room to room on the first floor, Helen followed and together they searched every inch of the place for a clue to a concealed door. At last they came to the conclusion there was none.
"You know, it could be in the cellar," Nancy suggested.
"Well, you're not going down there," Helen said firmly. "That is, not without a policeman. It's too dangerous. As for myself, I want to live to get married and not be hit over the head in the dark by that ghost, so Jim won't have a bride!"