That's How They Got Capone - S1.E12

Mr. Brahms decides to have a tax filing party at work. Peter signs his and says he will take it home for sick, bed-ridden Greta to sign. Mr. Brahms sends Peter home to care for her and then shows up with flowers. Greta is forced to sign the return and then Mr. Brahms takes it and mails it. Peter and Greta pose as filmmakers to talk to an IRS agent to get ideas on how to retrieve their return, saying it's a movie plot. They finally go back to the IRS, a different agent, and partially telling the truth, manage to substitute Peter's real tax return for the bogus one. Mr. Brahms tells Peter the next day that he has decided to make the tax filing party a yearly benefit.