I am helping out a family member with recovering their domain name for their business and wanted to seek some advice.

Situation:
They had an ad agency make a website for them. The domain was registered by the agency in their name. The agency has gone out of business, the phone numbers are not answered, and the agency's domain has been picked up by domainers/squatters (it is being parked now).

How is the best way to get the domain back in their control before it expires this summer? Waiting for it to drop or choosing a new name isn't an option because the domain is widely used.

Thanks