Pandavas suspect

Bhima said he was able to smell oil and butter and he was suspecting someone wanted to burn them alive in that house. Yudhistira said maybe that was the reason Vidura had tried to warn him in the language of mlechhas.
Bhima said it was time to go back to Hastinapura. Yudhistira said that was not correct. It would spread amongst the people. Duryodhana would twist the story to show Pandavas in bad light. He would call for a war and we would be defeated, It was best to lie low and escape after a few days into the forests.
In Hastinapura, Vidura was wondering how to save the Pandavas. He caught hold of a trusted tunnel digger and instructed him.
As per the instructions, the digger went to Yudhistira and told him about the house and also said as per Vidura's instructions, he would be digging a tunnel.
Work started. A nice door was built and set at the mouth of the tunnel. From the outside, no one could make out that a tunnel was being dug there. In the day time, Pandavas would roam around in the jungle and go hunting. In the nights, they would work with the digger and help in the tunnel construction work.
For months Pandavas stayed there, and slowly Purochana started believing that the Pandavas suspected nothing.
One day they discovered that Purochana was planning to set fire the next day. The Pandavas decided to set fire to the house that very night. Kunti said she wanted to host a feast and feed the poor and the brahmanas. Along with others, there came a hunter woman and five sons. All had their fill and rested there in the palace.

Pandavas in Varnavrata

When Duryodhana heard that the Pandavas would be going to Varnavrata, he called Purochana, trusted aide of his. Purochana was a Yavana man and Duryodhana trusted him very much. Duryodhana told Purochana that whatever would be discussed there, should not be let out to anyone at all.
He said before the Pandavas left for Varnavrata, Purochana was to leave for Varnavrata before the Pandavas. He was build a house there which was to be built with highly combustible material. It was to be camoflaged such that no could make it out.
Anyone who came in and went out of the house were to be closely monitored. Moats were to be dug around the house. The moats were to be deep and also wide such that one could not cross it by jumping across. When the time was right, the house was to be set on fire.
Purochana left to accomplish his task.

In Hastinapur, Pandavas started taking leave of the elders as they would be away for sometime in Varnavrata.
The people in Hastinapur started bad mouthing Dhritarashtra. They some how suspected that the Kauravas were upto no good. They rushed to see the Pandavas leave for Varnavrata, not sure when they would see them next. Many wanted to go with them.

When the Pandavas were leaving, Vidura spoke to Yudhistira in a language only the two knew, the language of the mlechhas. He asked them to be careful and beware of fire.

Seeing the Pandavas, Purochana came to welcome them and invited them to stay in the palace that had been constructed for them. The Pandavas entered the house were happy to see it. Yudhistira asked Bhima to silently inspect the house as he felt there was something wrong with the house. 

Yudhistira hears about Varnavrata

With Yudhistira made the crown prince, people of Hastinapur were very happy. He was kind and just. They wanted him to be the future king. Bhishma could not be king because of his promise; Dhritarashtra because of his sight.
Duryodhana could not stand this. He went to his father and wanted a way out. He told him people did not respect him because of his sight. They wanted Yudhistitra as the king. If Yudhistira became king, then his son and their sons would be kings and no one would listen to Duryodhana and his brothers.

The king called  Dushshasan , Karna and Shakuni and asked them what to do. They said send Pandavas away in some ruse.

Dhritarashtra wanted to know what would be the reason for Pandavas to go away.  Duryodhana said there was a wonderful land called Varnavrata. The Pandavas could be asked to visit that place.  They could stay there for sometime while Duryodhana ruled. Once the visit was over, Pandavas could come back and take over the kingdom.

Dhritarashtra said think of a way in which the Pandavas would themselves want to go to Varnavrata and not asked to go there. If they were forced to go, Bhishma and others would go against him.

Duryodhana said he will think of a way to accomplish this. He first went to the ministers, and by gifting them rich gifts, he gradually bought them over to his side. He coached them to talk about Varnavrata as a paradise on earth, and the ministers started doing that.

Afew days later, was the day of Shivaratri. A grand celebration was held as Varnavrata to enhance its popularity.

Hearing about the festival and also hearing about the greatness of the place, Yudhistira decided to visit Varnavrata.

When Dhritarashtra heard this he was very happy. His plan was succeeding. He told Yudhistra to go with his brothers and mother and visit the place.