Roger Greenberg [Ben Stiller], single, fortyish and at a crossroads in his life, finds himself in Los Angeles, house-sitting for six weeks for his more successful/married-with-children brother. In search of a place to restart his life, Greenberg tries to reconnect with old friends including his former bandmate Ivan [Rhys Ifans]. But old friends aren’t necessarily still best friends, and Greenberg soon finds himself spending more and more time with his brother’s personal assistant Florence [Greta Gerwig], an aspiring singer and also something of a lost soul. Despite his best attempts not to be drawn in, Greenberg and Florence manage to forge a connection, and Greenberg realizes he may at last have found a reason to be happy.